Wednesday, July 2, 2014

Interior Deluge

[Update 5 pm]  The 2-day total at Fairbanks airport stands at 3.37".  Significant rises are being observed and predicted for area rivers; by this time tomorrow the Tanana River at Nenana is expected to be quite close to a moderate flood stage:

[Update 10 am AKDT: with the event apparently winding down now, the 2-day total is up to 3.31", making this (so far) the 3rd heaviest 2-day event on record in Fairbanks.  According to the NOAA precipitation atlas, the average recurrence interval for this is about 50 years.  Brian supplied more statistics in the comments below.]

The third major rainstorm in a two-week period for the Alaskan interior is proving to be the heaviest, by far, for the Fairbanks area.  Rainfall since midnight Monday night has amounted to 2.67" at Fairbanks airport, and it's still falling heavily.  This is an extraordinarily high amount for interior Alaska; here are the top 5 non-overlapping 2-day precipitation totals for Fairbanks:

Aug 11-12, 1967   4.29"
Jul 26-27, 2003    3.43"
Jul 19-20, 1948   2.81"
Jul 1-2, 2014    2.67"+
Aug 27-28, 1930    2.40"

There will be much more to say when all is said and done, and I expect Rick and Brian will contribute other precipitation totals, but for now here is a map of 24-hour totals from the NWS mesonet page:


  1. It's an amazing event so far. There's 3.5" of precip in my USFS gauge since late Monday when it started, and more is forecast through today.

    I've lived in Southeast and Kodiak so rain isn't news...there. But for Interior Alaska this has to be a record event.


    1. Gary, here are some stats that I e-mailed Rick and Richard a short while ago.

      Through 9 a.m. the 2-day precipitation total is 3.28". This is the 3rd largest total on record. Here are the top 3 non-repeating amounts.

      1) Aug. 11-12, 1967 --> 4.29"
      2) July 26-27, 2003 --> 3.43"
      3) July 1-2, 2014* --> 3.28" (through 9 a.m.)

      Yesterday's official total of 1.92" is the 3rd largest total for any calendar day on record. As of 9 a.m., today's rain of 1.36" ties for 16th place.

      1) Aug 12, 1967 --> 3.42"
      2) July 27, 2003 --> 2.27"
      3) July 1, 2014 --> 1.92"
      T16) July 2, 2014 --> 1.36"

      All 24 hourly observations showed measurable precipitation on July 1st. The last time that occurred was February 10, 1996 (0.33" total). Good hourly observations go back to 1974.

      As of 9 a.m. there has been measurable precipitation for 33 consecutive hours. This ties for the longest stretch since 1974 (1996 and 2003). The record should be eclipsed next hour.

      At least 0.10" fell for 12 consecutive hours. Since 1974, the previous record was 5 consecutive hours which happened on four occasions.

      This is the fourth time that consecutive calendar days have received over 1" of precipitation.

      The 15-day total precipitation through 9 a.m. is 6.54". This is the largest 15-day total of record (normal annual total is 10.81").

      Through 9 a.m., the July total of 3.28" already makes July 2014 the 14th wettest July on record (out of 102).

    2. Great info Brian. Your analysis is always interesting. I'm proud to say I experienced the cow versus flat rock event and survived.

      Going forward I can't help but wonder and worry for others living in low areas adjacent to lakes and rivers. Maybe it'll dry out later in the month.

      Something else to ask. Where are the depths of soil water tables recorded? Or water well levels? I know they'll surely rise soon from precip impacting and descending terrain and nearby flows in rivers.


    3. Gary, I had a look around for ground-water level data but without success. I'm sure the rises will reflect those being seen on creeks and rivers.

  2. So we have had the most rain since '67? It will be interesting to see what the official numbers say. I read the online Newsminer article with updates. Funny seeing quotes from Rick that are also found here.

    All of this brings me to a question: how many general records gave been broken recently? In the 9 years I've been in Fairbanks it seems that we have been breaking more records recently - whether they be heat or cold, rain or drought, ice or wind storms. What is the rate of record breaking? And how many of each general category?

    1. Interesting question, Eric, regarding records. Brian showed that 2013 was the most "extreme" year in Fairbanks history in terms of daily temperature departures from normal, but not necessarily in terms of records being broken. It shouldn't be hard to pull up the information for at least temperature and precipitation.

  3. It's been wet here in South East also. The weather the last two-three weeks has been a series of moderate rain events. It seems like about 20 hours or so after the rain would hit here in the panhandle my wife back home in Fairbanks would tell me it was starting to rain there. In fact this latter half of June reminded me a lot of South East Alaska weather. Speaking of here (South East) last summer in June (the latter half) a weak little low rotated from the western pacific up through the Bearing sea, around the north slope, down through the Yukon and south through the panhandle. (Around the HUGE hot ridge that dominated last summers weather) When it arrived here it brought thunderstorms which are rare here. I've only seen them twice, once that June and the second time in October of 2010 when a strong occlusion came onshore. What weather pattern would support thunderstorms in the panhandle? With all the ocean water nearby surface heating and convection is nearly impossible to establish. They can at times form in BC and drift west but often fall apart over the mountains. I. The interior surface heating occurs easily, and with surface moisture (which is abundant now) I'd expect to see some thunder activity this week assuming the high that is building in does not have a strong capping inversion. Anyone care to tackle my panhandle question? Thanks for reading!

    1. Mike, thanks for the comments and question. I've no doubt you're right that the low-level coolness is very conducive to vertical stability and a lack of convection. So we would need either very cold air aloft or strong forced lifting, and ideally some of both.

      What's the closest airport weather station to your panhandle location? I'll take a look at the historical data to see what weather patterns have allowed thunder to occur in the past.

    2. Hey Richard. We are slightly closer to Haines than Juneau.