Fresh Snow in the Brooks Range

FAA webcam photo from Chandalar DOT camp on the Dalton Highway at 1220pm Saturday. Looks the fresh snow level is at about 4500' MSL.

It was NOT 97 degrees at Northway in July

Okay, I guess have have to say this: It was NOT 97 degrees at Northway in July.

There is a news story going around about record highs in all 50 states in July, including 97F at Northway on July 11th. 97F would be an all-time record high for Northway.

Except that the high temperature on July 11th at Northway was 77F.

The 97F high temperature was encoded in an observation, but the temperature sensor was bused (probably the aspirator fan failed). The FAA observers did correct the daily max temp after the original observation went out to the world.

Other high temps that day were in the upper Tanana Valley region were in the upper 70s and lower 80s.

Moral of the story is the same as always: constant vigilance.

Not Much Frost

Skies were never able to clear overnight so there was not much in the way of freezing temperatures in the Fairbanks area. The low at the airport was 44F, but even Goldstream Creek only got to 36F, which is nothing for there (they had 4 days in July with a min temp of 32F or less). Eielson AFB also got to 36F. The coop site at Mile 42 Steese Highway did report a low of 30F. To the north of Fairbanks there were less clouds, and Livengood RAWS reported a low of 28F, and 31F at Seven Mile, just north of the Yukon River on the Dalton Highway.

Now That's a Front

You say it must be getting on towards autumn when Rick starts putting up upper air plots? Well…

A well marked but essentially dry cold front moved through the Fairbanks area Friday mid-morning. We don't often see temperatures this time of year cooler at the surface at 3pm than at 3am in the absence of rain. The 850mb temperature was right at freezing at 3pm, not quite a record but still impressively cool for the first week of August.

Early August Sea Ice

According to the analysis of Arctic Sea Ice coverage by the National Snow and Ice Data Center, ice coverage for July was the lowest of record, even lower than 2007. However, during the last couple weeks of July the rate of ice loss decreased, and as of August 3rd the total coverage is no longer lower than the same date in 2007.



This is potentially good news, but the slower loss may not last. Figure 4 of the analysis, below, shows that there is a lot of first year ice that is still vulnerable to loss in the six or seven weeks that remain of the ice loss season.

Darkness

2am Thursday in Fairbanks: darkness at night, a novel idea.

Wind Clouds

Pretty view of lenticular clouds from Delta Junction Wednesday evening. Surface winds gusted to nearly 50 mph at Fort Greely on Wednesday, which is pretty unusual for this time of year even in Delta.

July Narrative Summary

Public Information Statement
National Weather Service Fairbanks Ak
1211 Pm AKDT Mon Aug 1 2011

...Fairbanks Weather Summary For July...

Weather in July was fairly typical for an Interior Alaska mid-summer...with no extremes of temperatures. Rainfall…as is often the case this time of year...was highly variable.

At the Fairbanks Airport...the average high temperature was 71 degrees and the average low was 52 degrees. The average temperature of 61.8 degrees was 0.7 degrees below normal. The highest temperature for the month was 81 degrees on the 22nd. the low for the month was 45 degrees on the 17th and 20th.

Rainfall was highly variable in the area. At the Fairbanks Airport...the total July rainfall was 1.70 inches...almost exactly the normal of 1.73 inches. Measurable rain fell on 16 days during the month...three days more than normal. Thunder was hear at the airport on three days in july...which is also about normal. However...Eielson AFB measured monthly rainfall of 1.39 inches...just barely half of normal. In contrast…the College Observatory cooperative station on UAF West Ridge recorded 2.18 inches of rain in July…which is a tenth of an inch above normal.

Other July rainfall totals include...

University West..........2.84 Inches
Aurora.........................2.68 Inches
Goldstream Creek.......2.63 Inches
Gilmore Creek............2.12 Inches
East Farmers Loop.....2.01 Inches
Keystone Ridge...........1.90 Inches
Fort Wainwright..........1.33 Inches
North Pole..................1.31 Inches
Salcha River At Bridge...0.95 Inches

Much more rain fell in the uplands well east of town...which caused the Chena and Salcha rivers to rise to near flood stage on July 6th. The cooperative weather station at 43 mile Steese Highway recorded 5.53 inches of rain for July...while the automated station near Angel Creek in the upper Chena basin recorded 4.83 inches. Along the Salcha River...an automated gauge about 20 miles above the bridge recorded 4.54 inches of rain.

A couple of wildfires started mid-month on the flats south of Fairbanks...and the Bonnifield #1 fire grew to over 6000 acres by months end. This fire brought smoke at times to the area...which
on a couple of days was thick around North Pole and Eielson AFB.

Looking ahead to august...normal temperatures start to decline noticeably. The normal high temperature falls from 70 degrees on the first to 62 by the end of the month. Normal low temperatures fall from 51 degrees on the first to 43 on the 31st. In the past 106 years...august temperatures in Fairbanks have ranged from a high of 93 degrees in 1994 to a low of 21 degrees in 1922. Low lying areas usually have the first frost of the season in August.

Normal rainfall is 1.88 inches. Snow is very rare at valley level in August...though it has occurred a few times. Accumulating snow has occurred in town just once in August. On August 29th
1922...three inches of snow accumulated in Fairbanks.

Possible sunshine declines by more than three hours...from over 18 hours on the first to less than 15 hours on the 31st. Darkness returns to Fairbanks skies for the first time since late
April...and the first northern lights of the season at often spotted during the last ten days of the month.

$$

RT Aug 11

Fire Season Winding down

This morning's Alaska Fire Service situation report has zero staffed fires in the state, with seasonal acreage burned at 290,600 acres. This is an increase of 28,000 acres since the end of June. There are still a few active fires in the state, including the Chitsia Mountain fire in the northwest part of Denali National Park and the Bonnifield #1 fire on the flats south of Fairbanks. However, with August knocking, 2011 is clearly not going to be a big fire year. It is likely that there will be some more burning, and the total acreage may well reach 300,000 acres by the end of the season. Indeed, numerical models are forecasting a moderate chinook wind event for Monday and Tuesday. Near the Alaska Range there has not been very much rain the past few days, so I expect both the above mentioned fires to grow.

More on Climate Normals

Here's a plot by Blake Moore of the Alaska Climate Research Center showing the location of all sites in Alaska with 1981-2010 normals. There are 203 stations here, a whopping 60% increase in the net number of stations that had normals for the 1971-2000 period. Note though the large areas with almost no stations, including the comparatively heavily populated Yukon-Kuskokwim delta.

Sweet Rain

All of Fairbanks-land has received some rain the past day or so, though amounts vary greatly. Tuesday morning a solid area of rain made it into the eastern portions of the area. In the afternoon thunderstorms developed along the eastern edge of the rain shield. Overnight, another area of steadier rain developed mostly north and west of town. The result of these features is a hodge-podge of rainfall amounts.

At the upper end is the coop observation from Steese Highway Mile 42, with a whopping 2.10 inches. Angel Creek RAWS recorded 1.03 inches, and the CWOP site near Weller School, 1 Mile Chena Hot Springs Road, reported 0.95 inches. The Munson Ridge SNOTEL in the upper Chena Basin received over an inch of rain, though much of the that came late Monday night and Tuesday morning.

The hydrograph (from Alaska-PacificRFC) for the Chena River at the Wendell Street Bridge shows no rise yet (as expected) and only a moderate rise over the next few days as water from the upper Chena basin works downriver.



At the lower end, where we would have like to see a soaking rain, on the Tanana Flats to help squash the Bonnifield #1 fire, there was not much. The Blair Lakes RAWS reported 0.15 inches of rain and the Gold King RAWS, southwest of the fire, reported 0.13 inches. Better than none, but a lot more is needed. The Bonnifield #1 fire is now up to 6449 acres and will likely to continued to smoulder until the snow comes.

More Siberian Heat

Not timely, but just to make sure I note it:

Last Monday, July 18th, Yakutsk had a max temp of 38.4C, 101F. Low was 18.9C, 66F
Amga the same day had a high of 37.9C, 100F.

Also on the 18th, Verkhoyansk, on the Yana River and one of the super cold places in winter, had 34.1C, 94F.

Clear Creek Fire

A couple of fires on the Tanana Flats flared to life this week, and really took off today with low RHs and gusty southwest winds. The plume has been evident on the Pedro Dome radar all day. Here's a photo from about 745pm ADT Saturday from the Alaska Climate Research Center webcam. This produced a dramatic plume from town and, in some places ashfall too. In a much too common story, the models are backing off from any significant rainfall anytime soon.

Update: According to AFS Sunday morning, this is the Bonnifield #1 fire, which grew to over 2000 acres on Saturday. The Clear Creek Fire is onyl a few miles away from Bonnifield #1, and it grew by a couple hundred acres.

Comparing Normals

One of the highlights of the new 1981-2010 normals is that NCDC has employed some fairly standard statistical techniques to develop normals for stations with much less than the full (or nearly full) 30 year period. In part this has become practical with the great increase in computing power over the past 20 years rather than any magical breakthrough in statistical or climatic understanding. That said, here are plots of the 1981-2010 daily normal max and min temperatures for Keystone Ridge (1600' MSL) and Goldstream Valley Bottom (500' MSL, known to NCDC as Ester 5NE). There stations are about nine miles apart in the same drainage, so this is about as close to an apples to apples comparison as there is.

For normal highs, temperatures, Goldstream Valley Bottom runs colder than the ridge from late October until late February.



For normal min temperatures, the valley is always cooler than the ridge, though of course the differences are much larger during the snow cover season.



The other feature of both plots is that for the first time, NCDC has utilized the actual daily values in computing the daily normals. Duh, you say? In the past, NCDC has used a simple spline function that basically mapped a smooth curve of the monthly means to the daily values. As a result, daily normals were simple sine curves that mostly varied in how sharp the extremes were. With these new normals, much more structure in the daily normals. Notice the flat stretch in normal max temperatures during late November and early December at Keystone Ridge.

Arctic Sea Ice at

Gee, what a surprise. As of this week, Arctic sea ice is at a record low minimum for the satellite era (since 1979), running just below 2007. Here is the Alaska-centric view from the University of Illinois. There is about 7 to 9 weeks left of the ice melting season, and 2011 will almost certainly either wind up with lowest or second lowest (behind 2007) minimum coverage.

Snow in Denali Park

Snow fell Monday in parts of Denali Park. Snow at Eielson Visitor Center (3600' MSL) in July is not unusual, perhaps an every other year event on average. Enough snow to close the road in July much less common. Snow at Headquarters, at 2000' MSL, has only occurred once since observations started 90+ years ago. That was in 2003, when there was an inch of snow at HQ.

No big surprise: 850 mb temperatures at Fairbanks were +2.2C 3pm Monday and +1.4C 3am Tuesday. These are low but not excessively so for mid-July. And warmer weather is on the way.

The New Normals are Here

Eagerly awaited by climate fans everywhere, the 1981-2010 normals were released by the National Climatic Data Center earlier this month. Starting August 1, these will replace the 1971-2000 normals in the United States. Here is a quick look at the new normals for Fairbanks and how they have changed from the 1971-2000 set.

The warming in winter continues as the cold winters of the early and mid 1970s have dropped off, and this set comprises almost entirely the warm phase of the PDO. The other big temperature change is in June. Although not large in absolute terms, it is the largest standardized change of any month. This reflects the fact that temperatures don't vary nearly as much in summer as in winter. This early summer warming directly ties in with increased fire seasons.

For precipitation, the only really dramatic change is in July, with a big bump up, enough to make July solidly the wettest month of the year. Traditionally, August in Fairbanks has been the wettest month of the year, but in fact Fairbanks has been near the eastern edge of the area in which August is the wettest month of the year, and that line has clearly shifted westward.

Siberian Heatwave

No, this is not a repeat of a post from last summer. Major heatwave building in central Siberia.

Yakutsk reported max temperature of 95F on Tuesday and 96F Wednesday (Alaska Time). Amga, southeast of Yakutsk had a high of 97F Wednesday.

The numerical models keep this going several more days at least.

Nice Evening in Fairbanks

A delightful Wednesday evening in Fairbanks. Sunny, 68F and pleasant breeze. Love it :)

Fire Creep

Tuesday morning's (July 12) situation report from the Alaska Fire Service states that acres burned this season in Alaska is now up to about 272,000 acres This is an increase of about 10,000 acres since the first of the month. No surprise, with more than 13,000 lightening strikes and several dozen new fires in the past two weeks. However, the pattern has changed and looks locked into a somewhat cooler and damper, but most definitely not thundery pattern for the next week. There were no lightening strikes at all in the state on Monday. Given this forecast, time is running out this to be a major (million+ acre) fire season in Alaska. Once it starts to get dark at night and relative humidities recover, it becomes much harder for fires to dramatically grow. Not impossible, as 2004 and 2005 showed, but those were record dry Augusts with big fires already burning, whereas today the biggest fire that is actively burning is the 3800 acre Lloyd fire, southwest of Tanana. Only two other fires over 1000 acres are actively burning in the state.

I sure hope I don't jinx it by saying this, but it's looking hopeful :)

Convective Rainfall

Slow moving thundershowers brought good downpours to parts of the Fairbanks area on Friday. As often happens with convective showers, amounts varied greatly over short distances. Some totals include:

Around town:
Fairbanks Airport #2: 0.86 inches (near the Airport Post Office)
Fairbanks ASOS: 0.52 inches
Aurora Coop: 0.28 inches (near Lemeta)
Fairbanks Midtown: 0.15 inches
UAF West Ridge: 0.10 inches
East Farms Loop: 0.08 inches
Fort Wainwright RAWS: 0.03 inches

North Pole area:
North Pole-KJNP: 0.13 inches
Woodsmoke: 0.08 inches
Eielson: 0.01 inches

North of town:
Goldstream Valley Bottom: 0.56 inches
Goldstream Creek: 0.30 inches
42 Mile Steese Hwy: 0.26 inches
Fort Knox Mine: 0.19 inches
Chena Hot Springs: 0.05 inches
Keystone Ridge: 0.04 inches

Big High Aloft: the North Pole Edition

Here is the 4am ADT Friday 500 mb analysis by Environment Canada. See that huge 585 dm high near 85N/170W? My friend and former colleague Stu Ostro has done some work with the NCEP reanalysis data (1948-2011), and finds that this is close to the highest 500 mb height of record in the 85-90N belt (exactly where it ranks will depend on how the numbers shake out in the reanalysis). What this translate to is that, as a first approximation, underneath the high, the average temperature in the airmass between the surface and 500 mb (about 18000 feet) is about as warm as it has been anytime in the past 63 years.

Update: according to the NCEP reanalysis, on Thursday Jul 07 the mean 500 mb height 85-90N was 5877 gpm. This breaks the previous record daily average of 5848 gpm set in July 1966

Arctic Sea Ice

The monthly National Snow and Ice Data Center analysis of Arctic sea ice coverage is out for June, and shows that the ice extent at the end of June is the second lowest of the satellite era record, just behind—last year. This morning's webcam shot from Barrow shows all the shorefast ice is gone.

It is a near certainty this year will be among the few lowest sea ice minimums of record, and certainly could exceed 2007.

Seward Peninsula Storm

Here's a statement Tuesday evening from my colleague Wes in Nome about the less than delightful weather for the 4th in my old hometown. This was the front end of Bering Sea storm that brought 40+ mph winds and soaking rains to Nome-land on Tuesday (4pm ADT Tuesday analysis from Environment Canada)

...FOURTH OF JULY 2011 IN NOME ONE OF COLDEST ON RECORD...

THE INDEPENDENCE DAY JUST CELEBRATED IN NOME, ALASKA WENT DOWN IN THE
RECORD BOOKS AS ONE OF THE COLDEST ON RECORD. THE TEMPERATURE
PLUMMETED TO JUST BELOW FREEZING AT 31 DEGREES JUST AFTER 6 AM MONDAY
MORNING...JUST ONE DEGREE SHY OF THE ALL-TIME RECORD FOR THE FOURTH
OF JULY OF 30 REACHED IN 1924. THIS MADE IT THE SECOND COLDEST
TEMPERATURE EVER IN NOME ON INDEPENDENCE DAY.

WHILE THE DAY BEGAN WITH A COLD SUN AFTER SUNRISE, CLOUDS MOVED IN
FROM THE SOUTH BY LATE MORNING AND THICKENED THROUGH THE AFTERNOON
BEFORE RAIN SET IN BY MID-AFTERNOON. THE RAIN MEASURED OVER A
QUARTER OF AN INCH (0.27 INCHES), MAKING IT THE ELEVENTH WETTEST
INDEPENDENCE DAY IN NOME IN OVER 100 YEARS OF RECORDS AND THE WETTEST
IN NOME SINCE 2003.

BY MIDNIGHT THE TEMPERATURE HAD MANAGED TO RISE TO 45 DEGREES,
ENSURING AN AVERAGE TEMPERATURE OF 38 DEGREES FOR THE DATE. WHILE
NOME HAD REGISTERED A COLDER TEMPERATURE ON THE FOURTH IN 1924, THE
INDEPENDENCE DAY 2011 EDITION IN NOME TIED FOR THE COLDEST AVERAGE
TEMPERATURE EVER...WITH THAT OF 1985.

DESPITE WHAT MANY MAY HAVE DESCRIBED AS A MISERABLE, VERY UNSUMMER-
LIKE WEATHER DAY ACROSS THE SOUTHERN SEWARD PENINSULA WITH EVEN A
COATING OF SNOW REPORTED SNEAKING DOWN TO MIDDLE ELEVATIONS OF THE
INTERIOR HILLS...NOMITES CELEBRATED IN TRADITIONAL FASHION ENJOYING
PARADES, FLAG-WAVING, GAMES, RACES, REINDEER DOGS, AND ICE CREAM.
HOWEVER, MANY DID SO THIS YEAR WEARING COATS, GLOVES, AND HATS.

The Longer View

Here's a plot from the Climate Prediction Center of temperatures and departures from normal for the past year at Fairbanks. The middle plot shows the 31 day mean departure. This smooths out the short-term "weather" variations and bring out seasonal length patterns: warm late last summer and autumn, then mostly cooler than normal winter and spring, and now near to a bit above normal.

Fairbanks June Wx Summary

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE FAIRBANKS AK
1245 PM AKDT FRI JUL 1 2011

...JUNE WEATHER SUMMARY FOR FAIRBANKS...
...MILD AND WET...

JUNE STARTED OFF WARM AND DRY...CONTINUING THE TREND FROM LATE MAY. THIS ALLOWED FOR SMOKE FROM INTERIOR WILDFIRES ON A FEW DAYS...BUT IN TOWN THE SMOKE WAS NOTICEABLY DENSE ON JUST ONE DAY. STARTING ON JUNE 9TH...SHOWERS AND THUNDERSTORMS BECAME MORE FREQUENT. THUNDER WAS HEARD AT THE AIRPORT ON FOUR DAYS IN JUNE...COMPARED TO AN AVERAGE OF THREE. THE LAST THREE DAYS OF THE MONTH SEEMED MORE TYPICAL OF AUGUST WEATHER IN INTERIOR ALASKA...WITH THICK CLOUD COVER AND PERIODS OF STEADY RAIN.

AT THE FAIRBANKS AIRPORT...THE AVERAGE HIGH TEMPERATURE WAS 70 DEGREES AND THE AVERAGE LOW 51 DEGREES. OVERALL...THE AVERAGE TEMPERATURE FOR JUNE OF 60.4 DEGREES WAS 0.7 DEGREES ABOVE NORMAL. THIS TEMPERATURE EXCESS WAS DUE TO WARMER THAN NORMAL OVERNIGHT LOW TEMPERATURES...WHICH WERE BOOSTED BY FREQUENT NIGHTTIME CLOUD COVER. ONLY ONE DAY HAD A TEMPERATURE ABOVE 80...BUT THE HIGH TEMPERATURE OF 88 DEGREES ON JUNE 25TH WAS THE HIGHEST JUNE READING SINCE 2004. THE LOWEST TEMPERATURE DURING JUNE AT THE AIRPORT WAS 43 DEGREES ON THE 5TH AND 10TH. SOME OF THE NORMALLY COOLER LOW LYING AREAS RECORDED LOW TEMPERATURES NEAR OR JUST BELOW FREEZING EARLY IN THE MONTH...INCLUDING 30 DEGREES AT GOLDSTREAM VALLEY BOTTOM AND 33 DEGREES AT WOODSMOKE NEAR NORTH POLE...BOTH ON JUNE 5TH.

THE MONTH STARTED OFF CONTINUING THE DRY WEATHER OF SPRING...BUT SHOWERS BECAME MORE FREQUENT AS JUNE WORE ON. MEASURABLE RAIN FELL ON HALF THE DAYS OF THE MONTH...SIGNIFICANTLY MORE THAN THE LONG TERM AVERAGE OF 11 DAYS WITH 0.01 INCHES OR MORE OF RAIN. AS IS TYPICAL FOR JUNE...DAILY RAINFALL VARIED WIDELY IN THE GREATER FAIRBANKS AREA...THOUGH MONTHLY TOTALS WERE SIMILAR. THE AIRPORT MEASURED 1.77 INCHES FOR JUNE...BY FAR THE LOWEST MONTHLY TOTAL IN THE AREA. HOWEVER...THIS WAS STILL ABOUT A THIRD OF AN INCH ABOVE NORMAL. MOST OF THE RAIN FELL DURING THE LAST WEEK OF THE MONTH. OTHER JUNE TOTALS INCLUDE...
GOLDSTREAM CREEK.................2.01 INCHES
UNIVERSITY WEST..................2.15 INCHES
UAF WEST RIDGE...................2.58 INCHES
GILMORE CREEK....................2.60 INCHES
SALCHA...........................2.61 INCHES
NORTH POLE.......................2.91 INCHES
EAST FARMERS LOOP................2.96 INCHES
40 MILE CHENA HOT SPRINGS ROAD...3.95 INCHES

MUCH HIGHER MONTHLY RAINFALL TOTALS WERE MEASURED AT HIGHER ELEVATIONS IN THE UPPER CHENA BASIN...INCLUDING 6.24 INCHES AT MUNSON RIDGE AND 4.53 INCHES AT MONUMENT CREEK NEAR CHENA HOT SPRINGS. HEAVY RAINS ALSO FELL IN THE UPPER SALCHA RIVER BASIN...WHICH PUSHED THE SALCHA RIVER UP TO NEAR FLOOD STAGE ON JUNE 26TH. FARTHER EAST...THERE WAS FLOODING ON THE GOODPASTER RIVER A COUPLE DAYS EARLIER.

LOOKING AHEAD TO JULY...THIS IS OFTEN THE WARMEST MONTH OF THE YEAR IN FAIRBANKS. THE AVERAGE HIGH TEMPERATURE IS 72 DEGREES AND THE AVERAGE LOW 53 DEGREES. IN THE PAST 106 YEARS...JULY TEMPERATURES HAVE RANGED FROM 99 DEGREES IN 1919 TO A LOW OF 30 DEGREES IN 1905. AVERAGE RAINFALL FOR THE MONTH IS 1.73 INCHES..AND MONTH THE WETTEST AND DRIEST JULYS OF RECORD HAVE OCCURRED IN THE PAST TEN YEARS. JULY IS THE ONLY MONTH OF THE YEAR THAT IT HAS NOT SNOWED IN FAIRBANKS. POSSIBLE SUNSHINE DECREASES FROM 21 HOURS AND 27 MINUTES ON THE FIRST TO 18 HOURS AND 18 MINUTES ON THE 31ST. DURING THE LAST WEEK OF THE MONTH IT WILL AGAIN BECOME DARK ENOUGH FOR THE BRIGHTEST STARS TO BE BRIEFLY VISIBLE.

Lightning Climatology: Most strikes in one day

I've been working on developing a climatology of lightning strikes in Alaska using the historical lightning data available on the Alaska Fire Service web site (23 years of data). Here is the plot of the most strikes in one day in the state, from June 15, 2005: just under 8900 strikes. Following long standing practice, a strike day runs from 6am to 6am, so this plots strikes from 6am ADT June 15th to 6am June 16th. It is ironic that on this, the max strike day of record, there are virtually no strikes over the Tanana-Yukon Uplands, the area of the state with highest climatological frequency of lightning.

Barrow Snow

The UAF Sea Ice Group's Barrow webcam is back up, just in time to show a skiff of snow accumulating Friday morning. Trace amounts of snow in Barrow in July are not unusual. There is still some sea ice left too. The broken nature of the sea ice for July one is typical for the "new normal", though 30 years ago this photo would have been more representative of late July or early August

Fairbanks Soaker

From Fairbanks northward there has been a decent amount of rain the past few days. Nothing extreme, but enough, over a long enough period of time to soak in and help boast soil moisture. Coming right before the 4th of July holiday weekend, the timing is good too. Here are some rough totals the past five days:

Angel Creek RAWS: 0.7 inches
Fairbanks Airport: 0.8 inches
Eielson AFB: 0.8 inches
Keystone Ridge: 1.4 inches
Munson Ridge: 2.3 inches
Chatanika River RAWS: 3.2 inches

As of this morning's situation report from the Alaska Fire Service, 262600 acres have burned in Alaska thus far this season. There's potentially still six weeks left in the active fire season, but a good soaking is a good way to be going into July

Midnight Sun

FAA webcam shot from Prudhoe Bay, looking north at 201AM, which is almost exactly solar midnight.

Ice View from Saturday

Here is a MODIS image from the Terra satellite of the northern quarter of Alaska and adjacent oceans, taken Saturday. This nicely shows the edge of pack ice, some shorefast ice and ice in some of the bigger lakes north of 71N. Oh yeah, and lots of green too!

Deep Storm in the Western Aleutians

This analysis from the Ocean Prediction Center valid 10 AM Saturday shows the strong storm that is now in the southern Bering Sea. A pretty deep low for late June, it brought gusts to around 50 mph at Shemya early Saturday, and similar winds Sunday morning to Adak.

Big Lightning Day

There were more than 4300 lightning strikes Saturday across a fairly narrow across the Interior stretching from the upper Tanana Valley to the upper Kobuk valley. In spite of deep moisture, rainfall amounts were mostly underwhelming, generally a quarter inch or less, though there were isolated reports of around an inch of rain. At Keystone Ridge, it thundered intermittently from 6pm to 11pm.

Rains in the Eastern Interior

Eastern Interior Alaska was soaked Wednesday night and Thursday with widespread moderate to heavy rain. Above are hydrographs from the Fortymile River at the Taylor Highway and Birch Creek near 101 Mile Steese Highway. The Fortymile is about to go over flood stage. The much smaller Birch Creek has already crested.

Total rainfall Wednesday and Thursday include…

Ben Creek RAWS (above Coal Creek on the Yukon River): 2.58 inches
Birch Creek RAWS (east of central above the Steese Highway Bridge): 1.43 inches
Chicken RAWS: 1.07 inches
Preacher Creek RAWS (northeast of Circle City): 0.81 inches

The rain got about as far west as the east side of Fairbanks, with most places east of town receiving around a tenth of an inch of rain early Thursday evening. There was no appreciable rain from Fairbanks westward.

Active Lightning Day

Deep moisture streaming westward from the northern Yukon fueled the most active lightning day of the season thus far, with more than 4000 strikes. Virtually all the strikes were in the far northeastern Interior. There was a fair bit of rain with these storms, but some fire starts are very likely.

Retreating Sea Ice

Here is a NOAA-19 Polar Orbiter photo (from NWS Alaska Region) taken early Monday afternoon, with clear skies over much of Arctic Alaska. The ice edge is very well defined, with only a little shorefast ice on the coast and a few chucks in the open southern Chukchi Sea large enough to show up in this 1.6 km resolution image. There is also a little ice left in Kotzebue sound south of Cape Espenberg. Needless to say, this is much less ice than use to be normal for mid-June. According to the National Snow and Ice Data Center, the total ice cover as of June 19th across the entire Arctic is easily the lowest ever since satellite measurement of Arctic ice cover started in 1979.

Soaking Rains Show Up in the Rivers

Here is a hydrograph of the level of the Chena River near the Wendell Street Bridge. The big rise late Thursday and Friday, more than three feet, is more than I would have expected, given that there wasn't that much rain. Even the Munson Ridge SnoTel, at 3100' MSL south of Chena Hot Springs got less than an inch of rain on Wednesday.

The Tall One

The mountain from Wonder Lake Rangers Station Friday morning.

In Lower Tanana Athabascam, Denaathi, in Koyukon Athabascan Denaali, "the tall one"

Drought Breaker?

All of the Fairbanks area has received rain over the past several days, but amounts vary widely, as is usual for this time of year. The wettest areas have been on the east side of town: North Pole picked up 1.1 inches of rain Tuesday and Wednesday. Much less on the northwest side of town, including here on Keystone Ridge and on the Hastings Fire. Just 0.14 inches of rain here Tuesday and Wednesday. The Airport has had 0.20 inches. So while not a drought breaker, the rain definitely helps in the short term. In order to squash the fire season, we need frequent rains over a several week period. Drought

Here is a photo looking north from our house about 130am ADT Thursday. In spite of it being 44F, mosquitoes were still nasty.

Summer Snow

Snow this Monday morning in the Brooks Range. Here's a 718am photo from the FAA webcam at Anaktuvuk Pass. The snow has made it onto the south side of the crest, with 34F and (evidently) mixed rain and snow at Arctic Village.






Updated:

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE FAIRBANKS AK
1023 AM AKDT MON JUN 13 2011
....SNOW OVER THE BROOKS RANGE

SNOW OVERNIGHT AND MONDAY HAS ACCUMULATED IN THE BROOKS RANGE. A
SMALL ACCUMULATION ON VEGETATION HAS OCCURRED AT THE CHANDALAR DOT
CAMP AT DALTON HIGHWAY MILE 239. AN AUTOMATED WEATHER STATION AT
THE TOP OF ATIGUN PASS ON THE DALTON HIGHWAY REPORTED ABOUT THREE
INCHES OF NEW SNOW AS OF 9AM MONDAY. SMALL ACCUMULATIONS HAVE ALSO
BEEN NOTED AT ANAKTUVUK PASS...TOOLIK LAKE AND THE SAG RIVER DOT
CAMP AT DALTON HIGHWAY MILE 306.

LIGHT SNOWFALL IN THE BROOKS RANGE IN JUNE IS NOT UNCOMMON AND
WILL MELT AT ROAD AND COMMUNITY ELEVATIONS THIS AFTERNOON AND
TONIGHT.

$$
RT JUN 11

Showers

Showers in the Fairbanks area on Saturday, as is often case this time of year, brought a wide range of rainfall amounts:

Fort Knox Mine: 0.44 inches
Aurora (Co-op): 0.21 inches
Fairbanks Airport: 0.16 inches
Keystone Ridge: 0.05
UAF West Ridge: 0.01 inches
Goldstream Creek: Trace

A Summer's Day

Nice view looking northeast from the Nenana Airport Friday afternoon. The higher humidites and rain Thursday have put a temporary damper on Interior Fires, though burning will pick up this weekend. As of Friday morning total acreage burned is now up to 242K.

Some rain better than no rain

Through Wednesday, June 8th, only 0.08 inches of rain at fallen at Fairbanks Airport since May 1st. This is the lowest total during that time since 1915. Rain has increased across the area Thursday morning, with some places, though not in town, picking up a tenth of an inch or more of rain. A few areas on the east side of Fairbanks are pushing a quarter inch. Not much, but we'll take all we can can, with the Hastings fire now up over 24000 acres.

Updated: as of late afternoon the rain is about over. Some totals since midnight included

Fairbanks Airport : 0.08 inches
Keystone Ridge: 0.08 inches
Caribou Peak: 0.10 (north of Poker Flats)
Goldstream Hills PWS: 0.17 inches
Fairbanks RAWS: 0.18 inches (on Fort Wainwright)
Bias Drive PWS: 0.22 inches (near Weller School)
Chatanika River RAWS: 0.26 inches (9 miles NW of Murphy Dome)
Gilmore Creek: 0.32 inches (near Fox)
Munson Ridge SNOTEL: 0.41 inches (south of Chena Hot Spring, 3100' MSL)

Not anywhere near enough, but it's a start.

Alaska Fire Seasons

Here a plot of total acreage burned in Alaska over the past 70 years. Plainly, a few big seasons are sandwiched between summers with much less activity. However, the frequency of "big years" has doubled since the late 1980s. This year is a near certainty to exceed a million acres, which would make this the first time in the period of record with three summers in a row with a million plus acres burned.

Fire Stats

There are now seven fires so far this season in Alaska that exceed 10,000 acres, the latest being the Hastings fire, just north of Murphy Dome. The total acreage burned as of Sunday morning was 213,619 acres. This is still short of the 260,024 acres that had burned last year by May 31st, though that was extreme for so early in the season. Photo of the Hastings Fire burning above the Chatanika River, taken Friday June 03, from InciWeb.

Chilly Morning

Updated:
Skies cleared Saturday evening and a dry air mass allowed rural valleys to cool sharply. Overnight lows included 29F at Angel Creek RAWS, 30F at both the Goldstream Creek and Goldstream Valley Bottom co-ops and 34F at the PWS in Woodsmoke subdivision near North Pole (North Pole co-op 37F). Not as cold in more urban areas and at elevation, with 43F at Fairbanks Airport and 46F at Cleary Summit

Shorefast Ice at Barrow

Here is the view from Barrow Saturday evening June 4th. The shorecast ice is holding, with meltwater on top. The dark line at the horizon in the upper left is the open water beyond the shorefast ice. Image from the UAF Sea Ice group.

Another May Stat

For Fairbanks, not only was May 25-31 the warmest May week of record, but the second half of the month, May 16-31, was the warmest second half of May of record, with a mean temperature of 62.4F. For the the five warmest second halves of May have occurred since 1990.

May: Consistently Dry, Bipolar Temperatures

Fairbanks Airport wound up with 0.04 inches precip for the month of May, making this the driest May in the Weather Bureau/NWS era (since 1930) and the third driest since 1905 (the 1971-2000 normal is 0.64 inches). However, because all the precip was showery, even early in the month, amounts varied significantly, though everywhere was below normal. Here on the ridge, the monthly total of 0.38 was only the lowest since 2003.

Temperatures though flipped right at mid-month, going from near to below normal through the 15th then consistently much above normal thereafter. The average temperature the last week of the month of 66.7F is the warmest May week of record in 106 years of obervations.

A Cooling Thought

And now for something completely different: average temperature at the Amundsen–Scott South Pole Station in May was -80.7F, making this the coldest May of record there. The high temperature for May was -56F, the low -103F.

New Fire

Brand new fire just northeast of Murphy Dome down along the Chatanika River, about eight miles north of home here on Keystone Ridge. Another fire in Washington Creek beyond the Chatanika. Photo taken about 15 Mile Murphy Dome Road about 245pm. Arrgg…

Snow and Ice, or Lack Thereof

Here is a 500 meter resolution MODIS image from 255pm Sunday of northern Alaska. There is still a fair bit of snow cover close to the Beaufort Sea coast, and a lot of open water in both the Beaufort and Chukchi Seas for so early in the summer. According to the University of Illinois' Cyrosphere Today website, in both regions, areal ice cover is now 10 to 20 percent below the 1979-2008 average.

Early season Heat

Bettles set a new record high Saturday with a high of 83F. Tanana reported a high of 89F but that may be bogus: the highest hourly temp was 84F. Fairbanks had 86F, not a record.

Here on Keystone Ridge, the high of 83F is the warmest of record in 15 years of obs, and the low was only 64F, also a new record for May here.

Cooler today as the thermal trough as re-centered over the northeast Interior and a southwest breeze has developed. This has the added benefit of clearing out all the smoke, at least for the time being,

Revealing Photo

Here is the NOAA-19 Polar Orbiter visible image from 122pm ADT Saturday. Lots of interesting stuff on here. Fairbanks is near the northern edge of the smoke from the Volkmar East fire. Cumulus building over the Tanana-Yukon uplands. On the North Slope there is still some snow cover. Of more import though is the vast amount of open water now showing up off the North Slope coast.

Heat and Strong Inversions

The high of 85F on Friday at Fairbanks International easily broke the previous record of 82F set way back in 2010, and was the warmest May temperature since 1995. Most long term observation sites also set record highs, including 85F at Tanana, 82F at Bettles and 79F at Fort Greely (where some from the Volkmar East fire may have kept temps a couple degrees cooler).
Based on data since 1918, the 85F at Tanana appears to have tied the all-time May record high temperature.

Other high temperatures included 86F a Goldstream Valley Bottom, 84F at Nenana, 83F at North Pole and 79F here on Keystone Ridge.

In order to get this hot, fairly clear skies and a dry airmass are required, and these are the same ingredients needed for a decent nocturnal inversion. And lo, here are some low temperature Friday morning:

Salcha River RAWS: 30F
Goldstream Creek: 34F
Goldstream Valley Bottom: 36F
North Pole: 43F
Fairbanks IA: 49F
Keystone Ridge: 58F
Cleary Summit: 61F

So in spite of the fact the sun is up for 20 hours a day, we had an early morning inversion that would be respectable in December!

Record High at Fairbanks

83F at 5pm at Fairbanks International Airport: a new record high for May 27th.
Eielson AFB has had a high of 82F so far, tying the record for the date. More records will be set as the coop observations come in.

Here on the ridge, 79F so far.

The warmest non-RAWS temperature so far is 84 at Nenana. The upper 80s at various RAWS are sun effected due to the overly small, unaspirated radiation shield.

Sunrise at Fort Yukon

The sun peeks above the horizon at Fort Yukon. Photo from the FAA webcam at 254am ADT Friday.

Record High Temperatures Tied in the Fairbanks Area

The high temperature in Fairbanks on Thursday was 80F, tying the record set last year and several previous years. Likewise, the high of 79F at Eielson AFB tied the record high. The record high at Fairbanks and Eielson on Friday is 82F, and this is likely to be either tied or broken.
The Aurora cooperative in Fairbanks had 81F, which is the warmest official temperature so far reported.

Record High Temps on the Way

Temperatures will approach record high levels in the Interior over the next several days, but especially Friday, when some records are very likely to fall as the ridge aloft squashes convection. Saturday will likely be the warmest day, with low to mid 80s likely, but for locations that have observations going back to 1947, the 28th is generally the all-time record high for May, which is 90F, and hopefully that is out of reach!

Lightning Cranking Up

Wednesday was the most active lightning day so far this season, with just under 1300 strikes. The strikes on the Seward Peninsula are remarkably early in the season. Image from the Alaska Fire Service.

Summers are Starting Earlier in Fairbanks

Here is an update of some work I did a few years ago. The research question is: is summer, and the attendant threat of fires, starting earlier?

Since one warm day does not summer make, we need to use some threshold that integrates over a period of time. As a first crack I calculated daily 7-day running mean temperatures and then set the start of summer as the first day when this value was ≥55F. Offhand, this seems to me to be correlated with increased activity in the biotic world. By this criteria, the summer started in Fairbanks this year on Friday, May 20th.

What I've plotted here is then the 5 year running mean of this date, in order to smooth out the year to year variability. As you can see, there as been a fairly dramatic trend toward an earlier start of summer since the mid 1940s, even with the short-lived spike around 2000.

First 70 Degree Day on Keystone Ridge

Updated:
High temperature here on Keystone Ridge Tuesday was 74F, the first 70 degree day of the summer. This is almost exactly average for the past 15 years.

Rain, Whither Art Thou?

Here on Keystone Ridge, several long lasting showers moved through overnight, bringing a total of 0.20 inches of rain. I thought "Yeah, rain on the Moose Mountain Fire, and this will help moisten things up overall". Alas, we just got lucky.

Rainfall the past 24 hours are mostly 0.01 inches or less, including 0.01 at the Goldstream Creek cooperative station, less than two miles from the fire. North of Goldstream, most places received some rain, including 0.16 inches at Caribou Peak, north of Poker Flats, and 0.12 inches at the coop station at 43 Mile Steese Highway. Fairbanks Airport has received just 0.01 inches of precipitation this month; there is still more than a week left in the month, but for what it's worth, the record low precip for May is 0.01 inches set in 1915. The modern era record is 0.07 inches in 1957.

The Way Summer Comes

Green-up progressing up the south-facing slopes while snow patches cling to depressions on the north side of the ridge line.Photo Sunday afternoon from near the top of Murphy Dome, looking west-southwest.

Fire in Goldstream Valley

There is large fire burning up the north side of the ridge above Goldstream Valley, reportedly started by power lines arcing in the high winds. Photo by Julie M. looking from the IARC building looking north, about 440pm ADT

6pm Friday update: flames on the top of ridge clearly visible from IARC. This is very bad.

830pm Saturday update: 130+ people are working this fire, and it has been much less active today. Amazingly, apparently no injuries and no homes lost. However, unseasonably warm and mostly dry weather will continue for the indefinite future, which means this will be of concern for a long time to come.

Dramatic Dry Push

One of the more dramatic chinook-forced dry lines that I recall moved through Fairbanks on Friday afternoon. Note that sharp drop in dew point between 21 and 22 UTC (1 and 2pm ADT) and the spike in the winds. There was even one lightning strike just south of Livengood in the leading edge of the dry line.

Green-up in Context

With spring 2011 green-up now accomplished, here is a histogram of green-up dates at Fairbanks since 1974. Obviously, date of green-up is not normally distributed, rather, there is a sharp early peak followed by a long tail of later dates.

First 70F of the year: updated

The high Tuesday evening at the Fairbanks International Airport was 73F. So while the first 60 degree temperature, which was on Saturday, was more than two weeks later than average, the first 70 degree day was three days earlier than average.

The warm weather spurred a very dramatic green-up Tuesday afternoon all around town.
Instant summer.

FAA WebCam at Central

New FAA Webcam at Central came online last week. Here's the north-looking cam Tuesday afternoon. Nice view.

Green-up Pending

A few trees around UAF are starting to leaf-out now, and with well above normal temperatures forecast for the rest of the week, green-up should occur in the next few days. Green-up of West Chena Ridge as seen from UAF has been recorded since the mid-1970s. This year will be latest green-up since 2002.

First 60 Degree Day in Fairbanks

The high temperature Saturday in Fairbanks was 65F, the warmest day of the year so far and the first day it's been 60F or higher. This is two weeks later than the mean date for the first 60 degree temperature of the year. Since 1970, only twice has the first 60 degree temperature been later than May 14th. Here on Keystone Ridge, the high was 57F, and in the nearly cloud-free sunshine the snow patches decreased notably. The mild weather should allow for green-up to be sometime this week. Of course, in the northern Interior, spring has a ways to go. Here is a Sunday morning photo from the FAA webcam at Arctic Village.

Cool start to May

I missed some cool weather while I was gone. Here is a plot of max and min temperatures and daily departure from normal for Fairbanks thus far this month. Here on Keystone Ridge there are still plenty of patches of snow around.

Cool weekend?

I'll be back East visiting family for a week, so little or no blogging. Could be a cool weekend here.

Barrow Twilight

Continuous sunshine at Barrow is still a week away, but it's plenty light overnight. Here's looking northwest at 138am Monday, from UAF's sea ice camera.

April Weather Summary

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE FAIRBANKS AK
1113 AM AKDT SUN MAY 1 2011

...FAIRBANKS WEATHER SUMMARY FOR APRIL...

...A VERY NORMAL MONTH...

TEMPERATURES FOR APRIL IN FAIRBANKS AVERAGED ALMOST EXACTLY
NORMAL. SOMEWHAT COOLER THAN NORMAL WEATHER AT MID-MONTH WAS
BALANCED BY WARMER THAN NORMAL TEMPERATURES THE LAST 10 DAYS OF THE
MONTH. OVERALL...THE AVERAGE HIGH WAS 44 DEGREES AND THE AVERAGE
LOW WAS 20 DEGREES. THE AVERAGE TEMPERATURE OF 31.8 DEGREES FOR APRIL
WAS JUST 0.1 DEGREES ABOVE NORMAL. THE HIGH TEMPERATURE FOR THE
MONTH WAS 59 DEGREES ON THE 23RD AND 24TH. THE LOW WAS 15 BELOW ON
THE FIRST.

PRECIPITATION WAS CHARACTERISTICALLY LIGHT. AT THE AIRPORT THE
TOTAL PRECIPITATION WAS JUST 0.07 INCHES FROM 1.7 INCHES OF SNOW
ON THE 7TH AND 8TH. TOTAL PRECIPITATION WAS SOMEWHAT HIGHER IN
OTHER PARTS OF THE AREA...INCLUDING 0.16 INCHES AT THE UNIVERSITY
OF ALASKA...0.17 INCHES IN GOLDSTREAM VALLEY AND 0.28 INCHES AT
KEYSTONE RIDGE.

THE WINTER SNOW PACK SLOWLY MELTED AWAY DURING THE MONTH...AND WAS
GONE AT THE AIRPORT BY THE 27TH. THIS IS ONLY A FEW DAYS LATER
THAN THE LONG TERM AVERAGE. WITH NIGHTTIME LOWS NEAR OR BELOW
FREEZING THROUGH THE END OF THE MONTH...BREAK-UP ON AREA RIVERS
WAS ONLY SLOWLY GETTING UNDERWAY...NO SIGNIFICANT ICE JAM FLOODING
PROBLEMS THUS FAR THIS SPRING.

LOOKING AHEAD TO MAY...WARMING CONTINUES AS THE SUN GETS HIGHER IN
THE SKY EACH DAY. AVERAGE HIGH TEMPERATURES INCREASE FROM 52 ON
THE FIRST TO 65 ON THE 31ST. AVERAGE LOW TEMPERATURES INCREASE
FROM 30 ON THE FIRST TO 44 AT MONTHS END. IN THE PAST 104
YEARS...MAY TEMPERATURES HAVE RANGED FROM A HIGH OF 90 DEGREES IN
1947 TO A LOW OF 1 BELOW IN 1964.

NORMAL MAY PRECIPITATION IS 0.60 INCHES...NEARLY FOUR TIMES THE
APRIL AVERAGE. MOST OF THIS FALLS AS RAIN...AS TWO-THIRDS OF MAYS
HAVE NO MEASURABLE SNOWFALL. ON RARE OCCASIONS SIGNIFICANT SNOWFALL
CAN OCCUR IN MAY...AND ACCUMULATING SNOW EARLY IN THE MONTH IS MUCH
MORE COMMON AT HIGHER ELEVATIONS. OVER THE PAST 80 YEARS...MAY
SNOWFALL HAS EXCEED THREE INCHES JUST FOUR TIMES IN FAIRBANKS.

POSSIBLE SUNSHINE INCREASES FROM 17 HOURS ON THE FIRST TO OVER 20
HOURS BY THE END OF THE MONTH. BY MID-MONTH ENOUGH TWILIGHT
PERSIST ALL NIGHT TO ALLOW FOR MOST OUTDOOR ACTIVITIES.

$$
RT MAY 11