Winter Hangs on

Temperatures are warming up across northern Alaska and snow cover is starting to go at low elevations even on the North Slope and Bering and Chukchi Sea coasts. Not so much yet though at higher elevations in of the Brooks Range. The photo at the right taken Sunday morning is from Ivotuk, southwest of Umiat at about 2000 feet elevation.

Warming Up

Temperatures so far this this month have been significantly below normal, as the updated standardized daily temperature anomaly chart at the left shows. Through Wednesday, the high temperature at the Fairbanks Airport for the spring has been 61º on April 16th and again on May 12th. However, that's set to change as the first really warm weather of the season is in the cards, as high pressure aloft builds and has already put an end to the daily convection. Over the past 80 years the mean date for the first 70º temperature in Fairbanks is May 21st, and this year will be very close to that date. 

Cool May Morn

Temperatures fell overnight as skies cleared and the airmass remains on the cool side. Low temperatures Monday morning were near or below freezing in much of Fairbanks-land, including

Updated...
Goldstream Creek: 22F
Eielson AFB: 28F
UAF West Ridge: 28F
Fort Wainwright: 30F
Fairbanks Airport: 30F
Keystone Ridge: 32F
Cleary Summit: 35F
 (Photo Monday morning courtesy of the Alaska Climate Research Center)

The snowpack is getting pretty dirty at Barrow, as this late morning photo  from the UAF Sea Ice groups shows. it's been a cool spring in Barrow, with the temperature the first nine days of May averaging 8 degrees below normal. On the bright side, Barrow had their last sunset of for the summer last night at 12:59am. The next time the sun goes below the horizon at Barrow will be at August first at 220am

Thunder in Fairbanks

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE FAIRBANKS AK
706 PM AKDT SAT MAY 5 2012
 ...THUNDER AT FAIRBANKS AIRPORT...
...EARLIEST IN 28 YEARS...

A 20 MINUTE THUNDERSTORM AT THE FAIRBANKS AIRPORT EARLY SATURDAY EVENING WAS THE EARLIEST THUNDERSTORM OF THE SEASON SINCE 1984...WHEN THERE WAS A THUNDERSTORM ON MAY 3RD. THUNDER IN THE FIRST HALF OF MAY IS NOT UNCOMMON OVER THE HILLS NORTH AND EAST TOWN...BUT IS QUITE UNUSUAL TO OCCUR SO EARLY IN THE SEASON IN THE FAIRBANKS BOWL. REPORTS OF UP TO ONE TENTH OF AN INCH OF RAIN AND SMALL HAIL HAVE BEEN RECEIVED FROM AREAS ON THE EAST SIDE OF TOWN. $$ RT MAY 2012

(Photo from the FAA's Ester Dome webcam looking southeast at 554pm ADT Saturday)

Chilly on the North Slope...but...

Low temperatures Saturday morning on the North Slope were nearly or a bit below zero, including zero at Barrow, 2 below at Kaktovik and 8 below at Anaktuvuk.

How unusual is this? Not at all. Over the past 50 years, the average date of the last zero temperature in the spring at Barrow is May 3rd.

Webcam photo looking northeast from the Barrow Airport, courtesy of the FAA.

Precip Type in Dry Air

Friday afternoon and evening brought convective showers to Fairbanks-land. However, with a dry and still cool-ish airmass in place, the form of the (light) precipitation that did occur was perhaps not as might be expected. There were a few reports of light rain in the Fairbanks bowl. However, snow was reported near the Chatanika River on the Elliott Highway, below 800 feet elevation. Here on Keystone ridge, it snowed between 330pm and 4pm, with temperatures no lower than 38F. Unsurprisingly, light snow was also reported on Wickersham Dome, elevation 2600 feet.

The graphic shows a plot of the 00Z May 05 Fairbanks upper sounding (heights are in geopotential meters: for practical purposes, just think of the y-axis as in meters). The freezing level was over 3000 feet above the ground. However, the elevation of the "wet-bulb zero" (the elevation that if you saturate the air the temperature would be at freezing) was only 1400 feet above the ground. In at least some of the precipitation shafts, the air was not saturated, allowing snow to fall perhaps as much as 2500 feet below the nominal freezing level.

Spring in the Brooks Range

Noontime Friday photo from Chandalar DOT Mile 239 on the Dalton Highway at 3000' elevation , courtesy of the FAA. With high temperatures below freezing, snowmelt has a long ways to go in the central Brooks Range.

Here's an update of the 2012 standardized temperature anomaly chart for here on Keystone Ridge. The mean temperature Wednesday of 21F was 2.5 standard deviations below normal, the most for any single day since the coldsnap before Thanksgiving. On Tuesday, Fairbanks Airport set a new record low max temperature of 32F.

It's a cold May morning in Interior Alaska, with most places having low temperatures in the teens and lower 20s. Here on Keystone Ridge the low 11F is the lowest temperature in 16 years of record here and probably the lowest May temperature since 1992. Other lows include: 15F at Goldstream Creek, 19F at UAF West Ridge, 19F Mile 43 Steese Highway, 21F at Fairbanks Airport and 22F at Fort Wainwright. Webcam photo from Bettles Tuesday morning, courtesy of the FAA

More on April

As Corey noted in the April summary, this was 13th warmest April of record. This was mostly due to the persistence mild weather, with the warmth mid-month being the only really outstanding daily anomaly. Here's a plot of daily high temperatures in April, normals and the daily departure from normal. From the 18th through the 29th there was hardly any daily to day change in the actual high temperature. However, because normals are rising steadily, overall the departure from normal lowered with time.

And below is a plot of the mean April temperatures in Fairbanks over the past century. The linear regression for the full period 1905-2012 (not plotted) shows an increase of about 5 degrees AND is statistically significant. However, nearly all of that trend has come since the PDO shift in 1976. There is no significant trend from 1905 to 1976.

April Summary

PUBLIC INFORMATION STATEMENT NATIONAL WEATHER SERVICE FAIRBANKS AK 451 AM AKDT TUE MAY 1 2012 ...APRIL WEATHER SUMMARY FOR FAIRBANKS... ...MILD AND DRY... FOLLOWING A COLD MARCH...APRIL CONTINUED THE TREND OF THE LAST 6 MONTHS OF ALTERNATING COLD AND WARM MONTHS AND WENT INTO THE RECORD BOOKS WITH WELL ABOVE NORMAL TEMPERATURES. THE AVERAGE TEMPERATURE OF 36.9 DEGREES WAS 4.4 DEGREES ABOVE NORMAL. IT ENDED UP AS THE 13TH WARMEST APRIL ON RECORD AT FAIRBANKS. THIS CONTINUED A RECENT TREND OF WARM APRILS. SIX OF THE WARMEST 10 APRILS HAVE BEEN OBSERVED SINCE 1990. FOR THE MONTH...THE AVERAGE HIGH TEMPERATURE AT THE AIRPORT WAS 50 AND THE AVERAGE LOW WAS 24. THE HIGH TEMPERATURE FOR THE MONTH OF 61 DEGREES WAS OBSERVED ON THE 16TH AND THE LOW FOR THE MONTH OF 8 BELOW OCCURRED ON THE MORNING OF THE 4TH. TWENTY-SIX OUT OF 30 DAYS THIS PAST APRIL HAD TEMPERATURES THAT WERE ABOVE NORMAL...WITH THE ONLY COLDER THAN NORMAL WEATHER FROM APRIL 2ND TO 4TH AND ON THE 30TH. THE WARMEST TEMPERATURE DEPARTURES FROM NORMAL OCCURRED AROUND MID MONTH...AND ON THE 16TH THE HIGH OF 61 DEGREES ESTABLISHED A NEW RECORD HIGH FOR THE DATE SURPASSING THE OLD RECORD OF 59 SET IN 1993. IT WAS ALSO THE EARLIEST 60 DEGREE TEMPERATURE AT THE AIRPORT SINCE 1997. THERE WERE 19 DAYS WITH A HIGH TEMPERATURE OF 50 DEGREES OR WARMER...WHICH WAS WELL ABOVE THE AVERAGE OF 11 DAYS. THE PERSISTENTLY MILD WEATHER COMBINED WITH PLENTY OF SUNSHINE TO MELT OUT THE SNOW PACK QUITE RAPIDLY. THERE WAS 20 INCHES OF SNOW ON THE GROUND ON THE MORNING OF THE 9TH THAT ALL MELTED AWAY BY THE 20TH. THE LAST DAY WITH AN INCH OR MORE OF SNOW ON THE GROUND WAS THE 19TH...WHICH WAS JUST 3 DAYS SHY OF THE AVERAGE DATE FOR THE LOSS OF THE WINTER SNOW PACK...WHICH IS APRIL 22ND. THERE WAS AN INCH OR MORE OF SNOW ON THE GROUND FOR A TOTAL OF 184 DAYS THIS WINTER...WHICH WAS ONLY 2 DAYS SHY OF THE LONG TERM AVERAGE. THIS PAST APRIL WAS DRY WITH ONLY 7 HUNDREDTHS OF AN INCH OF RAIN WHICH INCLUDED A TRACE OF SNOW AT THE AIRPORT. THE 7 HUNDREDTHS OF AN INCH OF RAIN WAS NEARLY A QUARTER INCH BELOW NORMAL...BUT DID NOT RANK AS ONE OF THE DRIEST APRILS ON RECORD. THERE HAVE BEEN MORE THAN 20 APRILS OVER THE YEARS WITH 5 HUNDREDTHS OF AN INCH OF LESS OF RAIN (AND MELTED SNOW). THE LACK OF PRECIPITATION WAS NOT LIMITED TO THE VALLEY AS MOST HIGH ELEVATION SITES AROUND FAIRBANKS ONLY HAD AROUND AN INCH OF SNOW THIS PAST APRIL. HIGHER ELEVATION SITES STILL HAD SIGNIFICANT SNOW ON THE GROUND AT MONTHS END...WITH 8 INCHES AT KEYSTONE RIDGE ON MURPHY DOME...AND 22 INCHES AT MUNSON RIDGE SOUTH OF CHENA HOT SPRINGS AT AN ELEVATION OF 3100 FEET. LOOKING AHEAD TO MAY...NORMAL HIGH TEMPERATURES RISE FROM 54 DEGREES ON THE FIRST TO 67 DEGREES ON THE 31ST. NORMAL LOW TEMPERATURES RISE FROM 31 ON THE 1ST TO 44 ON THE 31ST. MAY TENDS TO BE A FAIRLY DRY MONTH WITH THE LIKELIHOOD OF SHOWERS TYPICALLY INCREASING LATE IN THE MONTH. ON AVERAGE ONLY 6 TENTHS OF AN INCH OF RAIN IS OBSERVED. MOST YEARS THERE IS LITTLE OR NO SNOWFALL IN TOWN DURING THE MONTH OF MAY...BUT TWICE IN THE LAST 30 YEARS THERE HAS BEEN MORE THAN 6 INCHES OF SNOW...MOST MEMORABLE FOR LONG TIME RESIDENTS IN 1992 WHEN THERE WAS 14.1 INCHES OF SNOW. HIGHER ELEVATION SNOW ON THE HILLS AROUND FAIRBANKS IS NOT ALL THAT UNUSUAL IN MAY ABOVE 1500 FEET...ESPECIALLY DURING THE FIRST HALF OF THE MONTH. THE LAST FREEZING TEMPERATURES OF THE SPRING ON AVERAGE ARE OBSERVED AT THE AIRPORT AROUND MID-MONTH...BUT RURAL VALLEYS WILL TYPICALLY HAVE FROST ON CLEAR NIGHTS EVEN LATE IN THE MONTH. POSSIBLE SUNSHINE INCREASES FROM JUST OVER 17 HOURS ON THE 1ST TO 20 HOURS AND 29 MINUTES ON THE 31ST. SOME TWILIGHT IS VISIBLE ALONG THE NORTHERN HORIZON AT THE START OF THE MONTH...AND BY MID- MONTH THERE IS 24 HOURS OF USABLE DAYLIGHT. THE FORECAST FOR MAY FROM THE CLIMATE PREDICATION CENTER INDICATES THAT THERE ARE NO STRONG CLIMATE SIGNALS THAT WOULD INDICATE AN INCREASED CHANCE OF EITHER SIGNIFICANTLY ABOVE OR BELOW NORMAL TEMPERATURES OR PRECIPITATION. ...MONTHLY WEATHER SUMMARY FOR FAIRBANKS ALASKA... OBSERVED LAST MONTH...04/2012 OBSERVED RANK AVG MAX TEMP (F) 49.7 9TH WARMEST OF 107 YEARS AVG MIN TEMP (F) 24.1 22ND WARMEST OF 108 YEARS AVG TEMP (F) 36.9 13TH WARMEST OF 107 YEARS TOTAL PRECIP (IN) 0.07 26TH DRIEST OF 99 YEARS TOTAL SNOW (IN) T 81ST SNOWIEST OF 97 YEARS $$ CB/RT

Persistence

Here is a an updated plot of standardized daily temperature departures for Fairbanks thus far this year. Recall that standardized departures are simply a way of scaling the absolute departure from normal to reflect the typical variability for a given time of year Technically, it's the departure from normal divided by the standard deviation. In this case, the daily normal and the standard deviation are taken from the 1981-2010 NCDC normals. This month, the outstanding feature is the nearly unbroken persistence of the warm anomalies rather than any major daily extremes.

Tanana River at Nenana goes out

The ice broke on the Tanana River at Nenana Monday evening, tipping the tripod on the Nenana Ice Classic at 839pm ADT. This is the fourth earliest break-up of the ice on the Tanana since the Nenana Ice Classic started in 1917. Here is a plot of break-up dates since 1917. The black lines represent simple linear regression. From 1917 through 1976 there is no trend at all. Since 1977 (corresponding to the shift of the phase of the PDO from negative to positive), the trend is not (yet) statistically significant, due to the comparative small sample size since then. However, for the entire 96 years of record, the trend toward earlier break-up dates, by more than a week is significant.

Seasonal Snowfall Comparison

The snow season is not necessarily done with yet, but with mild weather here and the snow melted out in town, here is a comparison of total seasonal snowfall between the Fairbanks Airport and here on Keystone Ridge. The percentage of snowfall on the ridge compared to the airport is plotted by the orange line. As Keystone Ridge is more than 1000 feet higher elevation than the airport, it's no surprise that every year there is more snow on the ridge than the airport, and the 16 season average is 39 percent more on the ridge than the Airport. It is somewhat surprising that in some seasons the difference is not very great: in three of sixteen winters the difference is less than 20 percent. This reflects the fact that the transition season from rain to snow in the autumn is often abrupt, and that spring is usually quite dry, so contributes little to the seasonal total. The winters with the biggest percentage difference, this past winter and 2009-10, both resulted from Keystone Ridge receiving much more snow in one or more events when winds aloft were west to southwest, a favored direction for copious precipitation.

Snowpack Meltout

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE FAIRBANKS AK
257 AM AKDT FRI APR 20 2012

...FAIRBANKS WINTER SNOW PACK MELTS OUT...
...RIGHT ON SCHEDULE...

PERSISTENTLY MILD WEATHER AND PLENTY OF SUNSHINE THE PAST TWO
WEEKS HAVE NOW MELTED AWAY THE WINTER SNOW PACK IN FAIRBANKS. THE
LAST DAY WITH MEASURABLE SNOW ON THE GROUND AT THE FAIRBANKS
AIRPORT WAS APRIL 19TH. THIS IS VERY CLOSE TO THE LONG TERM AVERAGE
DATE FOR LOSS OF THE WINTER SNOW PACK...WHICH IS APRIL 22ND.

FAIRBANKS HAS HAD AN INCH OR MORE OF SNOW ON THE GROUND SINCE OCT
18TH...RESULTING IN 184 CONSECUTIVE DAYS WITH SNOW ON THE GROUND.
THIS IS AGAIN VERY CLOSE TO THE LONG TERM AVERAGE OF 186 DAYS.

SNOW COVER REMAINS AT HIGHER ELEVATIONS AND IN SHADED AND WOODED AREAS
EVEN AT VALLEY LEVEL. SNOW DEPTHS THURSDAY EVENING INCLUDED
19 INCHES AT KEYSTONE RIDGE...SOUTH OF MURPHY DOME AT 1600 FEET
ELEVATION...AND 29 INCHES AT MUNSON RIDGE...SOUTH OF CHENA HOT
SPRINGS AT 3200 FEET ELEVATION.

$$
RT APR 12

Chena Slush Out

Here's a somewhat fuzzy webcam photo looking south across the Chena River just before 8pm ADT Thursday from Front Street (image courtesy of Pro Music). There are some open areas but most of the water visible is water on top of ice.

AO and Alaska Temperatures

A reader asked if the yo-yo temperatures since last autumn are related to the Arctic Oscillation. Short answer, no.

Long answer:

For starters, the Arctic Oscillation Index is a way to describe (near) surface pressure patterns in the Northern Hemisphere at mid and high latitudes. However, as the plot below illustrates, the long term (1949-2012) correlation with surface temperatures in the cold season (Oct-Mar) are not very high over western North America and most of Alaska (the correlation is marginally significant over a small area over south-central Alaska).



For this past cold season, below is a plot of the daily AO index and the standardized daily mean temperature anomaly for Fairbanks (through April 13). As you can see, there was no patterning of the AO Index with how much above or below normal the temperature was in Fairbanks. Notice that the very cold weather in mid-November occurred with a somewhat positive AO, while the cold weather at the end of January occurred when the AO was at largest negative value of the whole winter. Similarly, the very mild weather in early December occurred with a strongly positive AO, while at the end of December the AO was again strongly positive but Fairbanks was considerably colder than normal. For the whole period (Oct 1-Apr 13), the correlation was functionally zero (0.02).

New Webcam

Yahoo! The FAA's webcam high atop Ester Dome, northwest of UAF, is finally online. Here's the southeast view from 418pm ADT Wednesday. There are also views looking north, southwest and west. You can plainly see Chena Ridge and the Tanana River.

Snowpack Meltout

With record heat in progress, and the snow depth down to 7 inches and going fast, here's a look at the winter snowpack meltout date since 1930. For this exercise, meltout date is the latest date with 1 inch or more snow on the ground which was preceded by a week of days with an inch or more of snow on the ground. This last bit is there to exclude the few years like, say, 2001, when the winter snowpack was gone by April 22nd, but there were two consecutive days with accumlating snow in early May that resulted in an inch on the ground on the morning of May 5th. For most of the period of record, this is the depth of snow on the ground early in the morning. The plot on the right shows this date for each year through 2011; the black line is the 5-year running mean. As you can see, since 1972 the winter snowpack has lasted into May only four times, though since the early 1970s there is no trend at all in meltout dates.

Meltout date this year will be April 17-19, so just a touch earlier than the long term average.

Hot April Heads-Up

The average temp the first half of April in Fairbanks was 30.1F, which is 3.0F above normal. Left is the updated plot of standardized daily mean temp departures for 2012, with the current warmth falling right in with yo-yo pattern we had all winter.

The 90% percentile April mean temps for Fairbanks (1905-2011 data) is 36.9F. In order for this month to make the top 10% warmest Aprils, the second half of the month would have to have a mean temp of 43.7F, which is 5.7F above normal for April 16-30th.

That's a tall order, but with the valley snowpack now going fast and the CFS and CPC weeks 1 and 2 guidance showing no end to the warmth, it looks to be within reach. Of course, six of the ten warmest Aprils of record have occurred since 1990.

Temperature Differences

Measuring the temperature of the air seems like a simple thing, but in fact getting an accurate measure is actually not so trivial. For meteorological/cimatological purposes we of course want to keep the sensor out of the sun (because we're interested in the temperature of the air, not the temperature of the thermometer). This is done by enclosing the thermometer (or temperature sensor) in some kind of enclosure. But you want to keep the air moving through the enclosure, otherwise the mere fact that there is an enclosure will impact the temperature of the air inside.

So, there are basically two approaches used. First, have a fan move air from outside the enclosure across the thermometer and then out, or design you enclosure so that air can move freely through. The fan approach is termed aspirated, the second is termed passive. Usually there is not not much difference, but conditions this week, with brilliant sunshine, a still solid snow cover and not much wind are producing small but consistent differences. The graphic above shows the high temperatures on Wednesday. As you would expect, aspirated sensors run a little bit cooler.

First 50F of the Year

Updated: The high temperature at the airport was 51F.

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE FAIRBANKS AK
426 PM AKDT TUE APR 10 2012

...HIGH TEMPERATURE HITS 50 DEGREES IN FAIRBANKS....
...FIRST 50 DEGREE DAY OF THE YEAR...

THE TEMPERATURE AT THE FAIRBANKS INTERNATIONAL AIRPORT ROSE TO 50
DEGREES AT 330PM TUESDAY AFTERNOON. THIS IS THE WARMEST IT HAS BEEN
THIS YEAR AND IS FIRST TIME THE TEMPERATURE HAS BEEN AS HIGH AS 50
DEGREES SINCE OCTOBER 14TH.

OVER THE PAST 80 YEARS...THE AVERAGE DATE OF THE FIRST 50 DEGREE
OR HIGHER TEMPERATURE IN THE SPRING IN FAIRBANKS IS APRIL 10TH.

$$
RT APR 12

Spring time Inversion

Clear skies overnight and a still solid snowpack helped a reasonably strong inversion to form overnight. Valley min temperatures were in the lower teens while higher elevations barely got below freezing. Some specific low temperatures include:

Goldstream Creek: 10F
Chena Hot Springs: 11F
Woodsmoke PWS: 13F (near North Pole)
Fairbanks Airport: 14F

Keystone Ridge: 29F
Nenana Hills RWIS: 31F
Cleary Summit RWIS: 32F

Sunny Sunday

View from the Keystone Ridge weather station on Sunday, looking east. Snow depth is at 28 inches. We've not completely lost the snow cover in April any time snow depth has been two feet or more on April 8th.

Anchorage Sets Snowfall Record

After much adieu…


PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE ANCHORAGE AK
740 PM AKDT SAT APR 7 2012

UPDATED WITH LATEST SNOW TOTAL

...ANCHORAGE SETS NEW SEASONAL SNOWFALL RECORD...

SNOW HAS TAPERED OFF TO FLURRIES AT THE NATIONAL WEATHER SERVICE
FORECAST OFFICE AND NO ADDITIONAL ACCUMULATION IS EXPECTED FROM
THIS STORM. AN ADDITIONAL 0.9 INCHES OF SNOW FELL BETWEEN 4 PM
AND 7 PM WHICH BRINGS THE TOTAL FOR THE DAY TO 4.3 INCHES.

THIS MAKES THE 2011-2012 WINTER SEASON THE SNOWIEST EVER WITH
A TOTAL OF 134.5 INCHES. THE PREVIOUS SEASONAL SNOWFALL RECORD
WAS 132.6 INCHES SET IN 1954-1955.

$$

SEB/CC

it's a Hot One

Yesterday was the warmest day since early October in Fairbanks-land. Some high temperatures included:

Woodsmoke: 50F (near North Pole)
Fairbanks Airport: 49F
Fort Wainwright: 49F
Goldstream Creek: 49F
Eielson AFB: 48F
Keystone Ridge: 45F

Fairbanks March Summary

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE FAIRBANKS AK
244 PM AKDT SUN APR 1 2012

...MARCH WEATHER SUMMARY FOR FAIRBANKS...
...COLD AND SNOWY...

FOLLOWING A VERY MILD FEBRUARY...THE WEATHER PATTERN OVER NEARLY
ALL OF ALASKA FLIPPED...AND MOST AREAS HAD WELL BELOW NORMAL
TEMPERATURES FOR MOST OF MARCH. FAIRBANKS WAS NO EXCEPTION.

THE AVERAGE TEMPERATURE OF 4.5 ABOVE WAS NEARLY SEVEN DEGREES
COLDER THAN NORMAL AND RESULTED IN MARCH...QUITE UNUSUALLY...BEING
COLDER THAN FEBRUARY. AS WAS THE CASE IN JANUARY...DAILY
TEMPERATURES WERE NOT EXCESSIVELY LOW...AS THERE WERE NO
TEMPERATURES EVEN CLOSE TO RECORD LEVELS. RATHER...THE PERSISTENCE
OF CHILLY TEMPERATURES WAS MOST NOTABLE. EVERY DAY BUT ONE FROM
THE 10TH THROUGH THE 23RD WAS TEN OR MORE DEGREES COLDER THAN
NORMAL.

FOR THE MONTH...THE AVERAGE HIGH TEMPERATURE AT THE AIRPORT WAS
18 ABOVE AND THE AVERAGE LOW WAS 9 BELOW. THE TEMPERATURE ROSE
ABOVE FREEZING FOR THE FIRST TIME SINCE BEFORE CHRISTMAS ON THE
27TH...AND THE HIGH FOR THE MONTH WAS 44 DEGREES ON THE 28TH. THE
LOW TEMPERATURE IN MARCH WAS 30 BELOW ON THE 5TH...WHICH IS VERY CLOSE
TO THE LONG TERM AVERAGE LOWEST TEMPERATURE IN MARCH. THERE WERE
EIGHT DAYS WITH LOWS OF 20 BELOW OR LOWER...A BIT MORE THAN IN AN
AVERAGE MARCH.

MARCH IS TYPICALLY A DRY MONTH IN FAIRBANKS...BUT NOT THIS YEAR.
TOTAL SNOW OF 14.7 INCHES AT THE AIRPORT MADE THIS THE THIRD
SNOWIEST MARCH IN THE PAST 45 YEARS. MOST OF THE SNOW CAME ON THE
5TH THROUGH 7TH...WHEN SOME PLACES NORTH AND EAST OF TOWN RECEIVED
MORE THAN 18 INCHES OF SNOW. THE SNOW WAS QUITE POWDERY...WHICH IS
USUAL FOR THIS TIME OF YEAR. THIS BROUGHT THE SEASONAL TOTAL
SNOWFALL UP TO 57.4 INCHES...ABOUT 4 INCHES BELOW NORMAL. THE SNOW
DEPTH REACHED 29 INCHES ON THE 8TH...THEN COMPACTED TO 22 INCHES
BY THE 31ST.

SOME PRECIPITATION FELL ON MORE THAN HALF THE DAYS IN MARCH. THE
SNOW MELTED DOWN TO 0.74 INCHES OF WATER...NEARLY THREE TIMES
NORMAL.

LOOKING AHEAD TO APRIL...NORMAL TEMPERATURES CONTINUE TO INCREASE
RAPIDLY. AVERAGE HIGH TEMPERATURES RISE FROM 35 DEGREES ON THE FIRST
TO 54 DEGREES IN THE 30TH. APRIL IS OFTEN QUITE DRY. IN THE PAST
20 YEARS...HALF THE APRILS HAD LESS THAN ONE TENTH OF INCH OF
PRECIPITATION. MOST OF WHAT DOES FALLS TYPICALLY FALLS AS
SNOW...THOUGH RAIN SHOWERS SOMETIMES OCCUR...ESPECIALLY THE SECOND
HALF OF THE MONTH. ON RARE OCCASIONS SIGNIFICANT SNOWFALL OCCURS
IN APRIL...THOUGH ONLY FIVE APRILS IN THE PAST 60 YEARS HAVE
RECEIVED MORE THAN 10 INCHES OF SNOW. THE WINTER SNOWPACK USUALLY
MELTS OUT IN TOWN DURING APRIL. THE AVERAGE DATE FOR LAST DAY WITH
AN INCH OR MORE OF SNOW ON THE GROUND IS APRIL 22ND.

APRIL IS OFTEN A SUNNY MONTH...AS POSSIBLE SUNSHINE INCREASES FROM
13 HOURS AND 41 MINUTES ON THE FIRST TO 17 HOURS ON 30TH. DURING
THE LAST WEEK OF APRIL...SOME TWILIGHT REMAINS VISIBLE IN NORTHERN
SKY ALL NIGHT LONG.

$$
RT APR 12

Springtime in Alaska

A lovely April 1st at Denali National Park. Headquarters has a snow depth of 25 inches...which is pretty close to normal. Webcam photo from the FAA.

An Unexpected Snow

A quick couple inches of snow this morning in parts of Fairbanks-land, though from North Pole southward there was very little. Webcam photo from the Alaska Climate Research Center on UAF West Ridge from around noon with the sun poking through the clouds.

Spring up North

It's been a cold March on the North Slope: though Monday the average monthly temperature at Barrow was about 9 degrees below normal. And this morning continues that trend. Here's a photo from Barrow (UAF Sea Ice webcam), with the school bus trundling along through a brisk -29F morning. Elsewhere on the Slope (through 7am ADT), lows include 43 below at Nuiqsut and Umiat, 42 below at Deadhorse Airport and 37 below at Atqasuk.

Temperature Anomolies

With more seasonable temperatures in place now, here's an update of the standardized daily anomalies this winter for Keystone Ridge through Friday. What a see-saw season it's been.

Winter Lives, Sort Of

A fresh injection of cold air sent temperatures falling in Fairbanks-land overnight, and in valley where the wind dropped off it was kind of like winter. Lows included:

Goldstream Creek: 24 below
Fort wainwright RAWS: 23 below
Eielson AFB: 17 below

Elsewhere in the Interior:
Beaver Creek RAWS: 30 below
Eagle Coop: 28 below
Toklat RAWS: 24 below

(Image from Arctic Village, 925am Wednesday, courtesy of the FAA)

Solar Spring is Here

Here's a plot of daily high temperatures over the past five weeks at Fairbanks Airport (475 feet MSL) and Keystone Ridge (1600' MSL). The green line is the difference between the two (Airport minus Ridge). Up through late February, high temperatures were consistently lower at the Airport than on the Ridge. Since the end of February, the rapidly increasing solar insolation is breaking the nocturnal temperature inversion almost every day now, and this is a useful definition of spring in Interior Alaska.

Still Chilly on the Slope

It's been a cold week on the North Slope. Lows Thursday morning include:

Nuiqsut: -47F
Umiat: -47F
Sagwon SnoTel: -46F
Deadhorse Airport: -45F
Ikpikpuk River: -45F
Otuk Creek: -44F
Camden Bay: -41F

Swinging Temperature Update

Here's an update showing mean daily temperatures and standardized departures for Fairbanks since October 1st. The alternating cycle of warm-cold looks to continue.

Nippy on the North Slope

Temperatures are in the 40s below on parts of the North Slope Saturday morning, along with a fresh breeze in some places. At 8am AST,

Nuiqsut: -48F, south wind 9 mph
Alpine: -45F, south wind 9 mph
Deadhorse: -45F, southwest wind 13 mph

While plenty cold, this is not all that unusual this time of year for the North Slope.

Photo from Umiat at 8am, at a brisk -43F.

Snow update

This photo gives an idea of the snowfall here in the past 36 hours.

Through 9am Wednesday, 23.1 inches of snow here at Keystone Ridge since 6pm Monday. The maximum 24 hour total was 18.7 inches, 10pm Monday to 10pm Tuesday, by far the highest 24 hour amount in the 16 years here on the hill. This also pushes the seasonal total up over 100 inches.

Other event total snowfalls include

14 Mile Chena Hot Springs Road: 14.9"
Goldstream Creek: 13.5"
College Hills 12.5"
UAF West Ridge: 11.0"
Woodsmoke 8.6" (through 10pm Tuesday)
Fairbanks Airport: 8.6" (through midnight Tuesday night)

I'll update as more observations arrive.

Snow update

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE FAIRBANKS AK
844 PM AKST TUE MAR 6 2012

...HEAVIEST SNOWFALL OF THE WINTER IN FAIRBANKS...

FAIRBANKS RECEIVED ITS HEAVIEST SNOWFALL OF THE SEASON SO FAR
YESTERDAY AND TODAY. AS OF 3PM TUESDAY...FAIRBANKS INTERNATIONAL
AIRPORT RECEIVED AN OFFICIAL STORM TOTAL OF 7.4 INCHES OVER THE
COURSE OF LESS THAN 24 HOURS...AND THE SNOW HAS BEEN CONTINUING TO
FALL THROUGHOUT THE EVENING.

HERE ARE A FEW STORM TOTALS SO FAR FROM SPOTTERS AROUND THE AREA
AS OF 8PM:

KEYSTONE RIDGE........................16.6 INCHES
14 MILE CHENA HOT SPRINGS ROAD........11.3 INCHES
GOLDSTREAM CREEK......................10.8 INCHES
COLLEGE HILLS..........................9.9 INCHES
UAF WEST RIDGE.........................9.1 INCHES
HAMILTON ACRES.........................8.5 INCHES
WOODSMOKE/NORTH POLE...................7.7 INCHES

SNOW SHOWERS WILL CONTINUE THROUGH TUESDAY NIGHT WITH ANOTHER 1 TO 3
INCHES EXPECTED THROUGH 9AM WEDNESDAY. SNOW IS EXPECTED TO TAPER OFF TO
FLURRIES BY MID MORNING WEDNESDAY.

$$

JM

Snow Update

As of 6pm AST Tuesday, there has been 15.6" of snow since 6pm Monday here at Keystone Ridge. This is the greatest 24 hour snow total in the 16 years of obs here. Occasional gusty winds, but no significant drifting today, even in open areas. Snow occasionally blowing off of trees in exposed areas. That's a lot of shoveling.

Chamber of Commerce Day in Barrow

Lovely early spring day in Barrow: sunny, 19 below, west wind 10 mph. Image courtesy of the UAF Sea Ice Group.

Fluff Storm

Powdery snow overnight in Fairbanks-land

So far, amounts include
Keystone Ridge: 9.8"
UAF West Ridge: 6.2"
Goldstream Creek: 5.0"

All these locations have snow-liquid ratios of 20-30 to one, which is very high for around a quarter inch of liquid.

Big Snowfall Differences

Here's a plot of cumulative seasonal snowfall (through March 03) for Keystone Ridge and the Fairbanks Airport. The snowfall on the ridge is close to normal; the airport is only about 77% of normal. This is the biggest difference between the two sites in the 16 years of observations on the Ridge. The NRCS snow course data for March 1st is dribbling in, and shows that the below normal snowfall is confined to an area from Fairbanks eastward into the upper Chena and Salcha Basins, while north and west of Fairbanks, snowfall is close to or even a bit above normal.

Same Old Story

Here's the standardized daily temperature departures for Keystone Ridge for this winter. The pattern continues.

Winter 2011-2012

Here's another chart of the roller coaster temperatures in Fairbanks winter 2011-2012.

February Summary

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE FAIRBANKS AK
159 AM AKST THU MAR 1 2012

...MONTHLY WEATHER SUMMARY FOR FAIRBANKS ALASKA...

IN A DRAMATIC TURN AROUND FROM JANUARY...FAIRBANKS TEMPERATURES
IN FEBRUARY WERE PERSISTENTLY MILDER THAN NORMAL. HALF
THE DAYS DURING THE MONTH HAD AN AVERAGE DAILY TEMPERATURE
10 DEGREES OR MORE ABOVE NORMAL...WHILE ONLY THREE DAYS WERE 10 OR
MORE DEGREES COLDER THAN NORMAL. THIS WAS THE MILDEST FEBRUARY IN
FAIRBANKS SINCE 2002.

OVERALL..THE AVERAGE HIGH TEMPERATURE AT THE FAIRBANKS AIRPORT WAS
17 ABOVE AND THE AVERAGE LOW WAS 5 BELOW. THE AVERAGE TEMPERATURE
FOR THE MONTH OF 5.9 ABOVE WAS 7.2 DEGREES WARMER THAN
NORMAL...AND A WHOPPING 32.7 DEGREES WARMER THAN THAN AVERAGE
TEMPERATURE IN JANUARY. ONLY ONCE...IN 1934...WAS A JANUARY TO
FEBRUARY AVERAGE TEMPERATURE INCREASE GREATER THAN THIS YEAR.

THE HIGH TEMPERATURE IN FEBRUARY AT THE AIRPORT WAS 31 DEGREES ON
THE 5TH AND THE LOW OF 35 BELOW OCCURRED ON THE 1ST. TEMPERATURES
DID CREEP A BIT ABOVE FREEZING IN PARTS OF THE AREA...ESPECIALLY
ON THE 9TH AND 10TH...INCLUDING 35 DEGREES AT NORTH POLE AND
37 DEGREES AT UAF WEST RIDGE.

SNOWFALL WAS NEAR NORMAL IN FEBRUARY...WITH 7.5 INCHES AT THE
AIRPORT. THIS MELTED DOWN TO 0.42 INCHES OF WATER...WHICH IS
EXACTLY NORMAL. SNOW DEPTHS VARIED THROUGH THE MONTH BETWEEN 18
AND 21 INCHES.

WINDS WERE CHARACTERISTICALLY LIGHT AT THE AIRPORT...AVERAGING
ONLY 2.3 MPH. THE PEAK WIND OF 23 MPH OCCURRED ON THE 2ND.

FOR THE MID-WINTER PERIOD...DECEMBER THROUGH FEBRUARY...LARGE
TEMPERATURE SWINGS WERE THE RULE...WHICH ALMOST COMPLETELY
BALANCED OUT. THE FIRST THREE WEEKS OF DECEMBER WERE THE WARMEST
OF RECORD. THE LAST DAYS OF DECEMBER UNTIL THE FIRST OF FEBRUARY
WERE CONSISTENTLY QUITE COLD...FOLLOWED BY MILD WEATHER MOST OF
FEBRUARY. THE AVERAGE TEMPERATURE FOR THE THREE MONTHS AT THE
AIRPORT OF MINUS 5.9 DEGREES WAS ABOUT 1.5 DEGREES BELOW NORMAL.
SNOWFALL FOR THE THREE MONTHS WAS VERY CLOSE TO NORMAL...BUT FOR
THE SEASON THE TOTAL SNOW OF 42.7 INCHES IS MORE THAN A FOOT BELOW
NORMAL DUE TO THE LOW SNOWFALL IN THE AUTUMN.

LOOKING AHEAD TO MARCH...RAPIDLY INCREASING SUNSHINE HELPS BOAST
TEMPERATURES. AVERAGE DAILY HIGH TEMPERATURES INCREASE FROM
18 DEGREES ON THE 1ST TO 34 DEGREES ON THE 31ST. AVERAGE LOW
TEMPERATURES INCREASE FROM 9 BELOW ON THE 1ST TO 8 ABOVE ON THE
31ST. IN THE PAST 105 YEARS...TEMPERATURES HAVE RANGED FROM A HIGH
OF 56 DEGREES IN 1994 TO A LOW OF 56 BELOW IN 1911. SNOWFALL IS
TYPICALLY LIGHT...AVERAGING LESS THAN 5 INCHES...AND HAS EXCEEDED
A FOOT ONLY TWICE IN THE PAST 40 YEARS. POSSIBLE SUNSHINE
INCREASES FROM JUST OVER 10 HOURS ON THE FIRST TO 13 AND ONE HALF
HOURS ON THE 31ST. THE FORECAST FOR MARCH FROM NOAA'S CLIMATE
PREDICTION CENTER CALLS FOR AN INCREASED CHANCE OF SIGNIFICANTLY
BELOW NORMAL TEMPERATURES FOR FAIRBANKS.

Closing Up Winter

Here's a plot of the daily average temperature at Fairbanks since Oct 01. For what I usually refer to as "mid-winter", December through February, the mean temperature (through Feb 27) of -6.0F is a bit below normal (-4.7F through Feb 27). This will be coldest December through February since, get this, way back in 2008-09.

Wild Swings Update

Here's the updated plot of standardized daily temperature departures for this winter (through Feb 24) at Fairbanks. While not extreme this month, the persistent warmth follows the pattern established in November.

Arctic Sea Ice

Arctic sea ice is within a few weeks of it's maximum extent. Here is the Alaska-centered view from the University of Illinois's Cryosphere Today:

http://arctic.atmos.uiuc.edu/cryosphere/

Sea ice extent is much above normal, while on the European side of the Arctic it's much below normal.

Nice February Day

A lovely late February day at Arctic Village: sunny and 13 below at 1pm

Fluffy Snow

Keystone Ridge through noon Wednesday: 1.4inches of snow melted down to 0.03" water. Snow so fluffy you can see through it. :)

Another Morning, Another Inversion

Here's the morning sounding from Fairbanks, showing a strong inversion. At 9am, Goldstream Creek was -14F and Keystone Ridge +20F. Solar heating is increasing rapidly but is still not enough to come close to breaking the inversion. Yesterday the high temperature at Fairbanks was +11F, ten degrees lower than on Keystone Ridge.

More on the Wild Temperature Swings

The monthly mean temperature in January at the Fairbanks Airport was 30.8F lower than the December mean, This is the largest drop between December and January in the Weather Bureau/NWS era (since 1930). The change from October to November, 2011 of -37.1F was the third greatest since 1930. Depending on how the rest of this month turns out, it is entirely possible that the change from January to February will be in the top five greatest increases.

Clear Skies at Night, an Inversion's Delight

Clear skies overnight have allowed a strong inversion to develop this morning. At 8am, -10F in Goldstream Creek and +24F here on Keystone Ridge.

How Warm Has it Been?

The average temperature at the Fairbanks Airport the first two weeks of February was +5.6F. This is about 10 degrees above normal, but is only the 17th warmest first half of February of record. Temperatures are not expected to show overall much change the next few days, though low temperatures will vary in valleys depending on overnight cloud cover.

February Sunrise

A pretty morning Thursday at Mentasta Pass on the Glenn Highway, south of Tok. Photo from the FAA webcam.

Wicked Inversion

Here's the 3am AST Monday sounding from Fairbanks Airport, showing a very sharp surface inversion. That's a temperature of +4F at ground level, and +32F just 32 meters up. At 8am AST, the temperature at Goldstream Creek was -5F, while most of the hill elevation sites were reporting temperatures near +30F.

The Yoyo Goes On

Now that the next "warm phase" of the winter is well underway for Interior Alaska, here's an updated plot of standardized daily temperature anomalies at Fairbanks. For the most part, it's been either one or the other. Since November 1st, 54% of the days (55 out of 102) days have had an average daily temperature 1.0 or more standard deviations from the mean. If temperatures were normally distributed (which in general is not the case), we would expect about 32 such days. In the El Niño winter of 2009-10, Nov 1-Feb 10 had only 24 days ±1.0 standard deviation from the daily normal. Got all that?

The Carved Out Ridge

Here's the Monday 11am AST GOES-15 infrared image. This nicely show the high aloft centered over the Yukon (with a small low embedded near Watson Lake).

As the Winter Turns

Here's an updated plot of daily average temperatures this winter at Fairbanks. The mild weather now in place will be modulated in the valley by strong inversions when skies stay clear and winds stay light, at for the next couple of days. At 11am Monday, temperatures are near zero in the valleys and just above freezing at higher elevations. And the sun is shining.

Cold Snap at an End

Cold Snap 2012 has come to an end, with nearly all of northern Alaska now above zero. Here's a UCAR plot of observations from 11am AST Sunday. The only large area still below zero is the western North Slope. There is a typical inversion over much of the Interior. At 11am in the Fairbanks area temperatures were in the single digits above zero, while higher elevations were in the upper 20s and lower 30s.

Big Swings

Here's a plot of hourly temperatures at Keystone Ridge since Wednesday. Find the time of frontal passage. The drop from 25F at 8pm to -1F at 10pm was accompanied by only a slight breeze: enough to tinkle the wind chimes, but that's about it.

January Cold Stats

Here's an abridged version of the statement highlighting the monthly records. The full version (for a while) is here.

NOAK49 PAFG 012052
PNSAFG
AKZ216-218>225-227-020915-

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE FAIRBANKS AK
1146 AM AKST WED FEB 1 2012

...JANUARY 2012 WAS A RECORD OR NEAR RECORD COLD MONTH FOR MUCH OF
CENTRAL AND WESTERN ALASKA...

ALL OF NORTHERN ALASKA WAS UNDER THE INFLUENCE OF A VERY COLD AIR
MASS FOR NEARLY ALL OF JANUARY. THE GREATEST TEMPERATURE DEPARTURES
FROM NORMAL OCCURRED ACROSS THE WESTERN INTERIOR WHERE THE SKY WAS
MORE PERSISTENTLY CLEAR...WHICH ALLOWED STRONG INVERSIONS TO FORM
AND TEMPERATURES REMAINED VERY LOW FOR A PROLONGED PERIOD OF TIME.
MANY COMMUNITIES ALONG THE WEST COAST AND ACROSS THE WESTERN
INTERIOR HAD THE COLDEST OR ONE OF THE TOP FEW MONTHS ON RECORD.
THE DURATION OF THE COLD WEATHER WAS MORE NOTABLE THAN THE
ABSOLUTE MINIMUMS...AS RELATIVELY FEW DAILY RECORD LOW TEMPERATURES
WERE SET AT LOCATIONS WITH MORE THAN 50 YEARS OF WEATHER
OBSERVATIONS.

AT NOME...THIS PAST JANUARY WAS THE COLDEST ON RECORD. THE
AVERAGE TEMPERATURE OF -16.6 DEGREES EASILY EXCEEDED THE OLD
RECORD OF -15.2 DEGREES THAT OCCURRED IN 1989. THIS WAS NOT QUITE
THE COLDEST MONTH OF RECORD...AS FEBRUARY 1990 HAD AN AVERAGE
TEMPERATURE OF -17.2 DEGREES. FOR COMPARISON...THE NORMAL
TEMPERATURE FOR NOME DURING JANUARY IS 5.2 DEGREES ABOVE ZERO. THE
LOWEST TEMPERATURE OBSERVED DURING THE MONTH WAS 40 BELOW ON THE
5TH. THIS WAS THE FIRST 40 BELOW READING AT NOME SINCE 1999.
TEMPERATURE RECORDS AT NOME DATE BACK TO 1907.

AT KOTZEBUE...JANUARY 2012 WAS THE SECOND COLDEST SINCE 1929. THE
AVERAGE TEMPERATURE OF -22.6 DEGREES IS THE COLDEST SINCE 1934...
WHEN THE AVERAGE TEMPERATURE WAS -27.7 DEGREES. CONTINUOUS
TEMPERATURE RECORDS AT KOTZEBUE DATE BACK TO 1929. THE LOW
TEMPERATURE OBSERVED DURING THE MONTH OCCURRED ON THE EVENING OF
THE 31ST WITH A LOW OF 45 BELOW. THIS WAS THE COLDEST TEMPERATURE
OBSERVED AT KOTZEBUE SINCE 2006.

AT GALENA...JANUARY 2012 GOES DOWN AS THE COLDEST MONTH OF
RECORD. THE AVERAGE TEMPERATURE OF -32.6 DEGREES SURPASSED THE
-31.4 DEGREES IN 1971. THE LOWEST TEMPERATURE THIS MONTH WAS 65 BELOW
OBSERVED ON THE 29TH. NOT ONLY WAS THIS A DAILY RECORD LOW...BUT
IT WAS THE 3RD LOWEST TEMPERATURE EVER OBSERVED AT GALENA. THE
ALL-TIME LOW WAS 70 BELOW BACK IN JANUARY 1989. THERE WERE ALSO
FOUR CONSECUTIVE DAYS WITH A LOW TEMPERATURE OF 60 BELOW OR COLDER
ON THE 28TH THROUGH THE 31ST. THIS WAS ONLY OUTDONE ONCE...IN
1989...WHEN THERE WERE SIX CONSECUTIVE 60 BELOW DAYS AT GALENA.
WEATHER RECORDS AT GALENA DATE BACK TO 1942.


AT MCGRATH...THE AVERAGE TEMPERATURE OF -28.5 IS THE COLDEST MONTH
OF RECORD. THE PREVIOUS RECORD WAS -27.5 DEGREES IN JANUARY 1989.
THE LOW TEMPERATURE IN JANUARY WAS 55 BELOW ON THE 4TH. WEATHER
OBSERVATIONS HAVE BEEN MADE AT MCGRATH SINCE 1939.

AT BETTLES...THIS PAST JANUARY ENDED UP AS THE COLDEST ON RECORD.
THE AVERAGE TEMPERATURE OF -35.6 DEGREES SURPASSED THE OLD RECORD
OF -34.0 IN 1971. THE LOW TEMPERATURE FOR THE MONTH WAS 61 BELOW
ON THE 31ST. THREE OF THE LAST 4 DAYS OF THE MONTH HAD A LOW
TEMPERATURE OF 60 BELOW...AND ALL THREE WERE NEW DAILY
TEMPERATURE RECORDS. THESE WERE THE FIRST 60 BELOW TEMPERATURES AT
BETTLES SINCE FEBRUARY 1999. WEATHER RECORDS AT BETTLES DATE BACK
TO 1951.

AT TANANA...THIS PAST JANUARY WAS THE COLDEST IN OVER A HUNDRED
YEARS WITH AN AVERAGE TEMPERATURE OF -32.6 DEGREES. ONLY 1906 WITH
AN AVERAGE TEMPERATURE OF -36.6 DEGREES WAS ANY COLDER. THE LOW
TEMPERATURE FOR THE MONTH OF 61 BELOW WAS OBSERVED ON THE 28TH.
ALTHOUGH NOT A RECORD...IT WAS THE FIRST TIME THE TEMPERATURE HAD
DROPPED TO 60 BELOW OR LOWER SINCE 1993.

AT DENALI NATIONAL PARK HEADQUARTERS...THIS WAS THE COLDEST
JANUARY SINCE 1933...WITH AN AVERAGE TEMPERATURE OF -18.6 DEGREES
AND IS 22 DEGREES BELOW NORMAL. THE LOWEST TEMPERATURE WAS 41 BELOW
ON THE 25TH. WEATHER OBSERVATIONS HAVE BEEN MADE AT DENALI
NATIONAL PARK HEADQUARTERS SINCE DECEMBER 1922.

AT FAIRBANKS...JANUARY 2012 WAS THE FIFTH COLDEST ON RECORD WITH AN
AVERAGE TEMPERATURE OF -26.9 DEGREES...WHICH WAS 19 DEGREES BELOW
NORMAL. IT WAS THE COLDEST JANUARY AT FAIRBANKS SINCE 1971...AND
RANKED ONLY BEHIND 1906...1934...1966 AND 1971. THE COLDEST
TEMPERATURE OBSERVED WAS 51 BELOW ON THE 29TH. TEMPERATURE RECORDS
AT FAIRBANKS START IN SEPTEMBER 1904.

EAST OF THE FAIRBANKS AREA THIS WAS GENERALLY ONLY THE COLDEST
JANUARY SINCE 2004, AND ON THE NORTH SLOPE...TEMPERATURES IN JANUARY WERE CONSIDERABLYBELOW NORMAL BUT WERE NOWHERE NEAR RECORD COLD.

$$
CB/RT FEB 12

The Way Cold Snaps End

Furiously warming aloft since mid-day Tuesday. The morning sounding tells the story. At 6am Wednesday, Cleary Summit+3F, Fairbanks Airport -34F