Climatological Report (Monthly) Issued by NWS Juneau, AK
000
CXAK57 PAJK 042029
CLMAJK
NATIONAL WEATHER SERVICE JUNEAU AK
1121 AM AKST THU JAN 04 2024
...................................
...THE JUNEAU CLIMATE SUMMARY FOR THE MONTH OF DECEMBER 2023...
CLIMATE NORMAL PERIOD: 1991 TO 2020
CLIMATE RECORD PERIOD: 1936 TO 2024
WEATHER OBSERVED NORMAL DEPART LAST YEAR`S
VALUE DATE(S) VALUE FROM VALUE
NORMAL
..............................................................
TEMPERATURE (F)
RECORD
HIGH 54 12/08/2017
12/23/1999
12/12/1944
LOW -21 12/31/1949
HIGHEST 48 12/30 44 4
LOWEST 23 12/19 5 18
AVG. MAXIMUM 39.5 34.7 4.8
AVG. MINIMUM 32.3 25.9 6.4
MEAN 35.9 30.3 5.6
DAYS MAX >= 90 0 0.0 0.0
DAYS MAX <= 32 0 10.1 -10.1
DAYS MIN <= 32 17 21.1 -4.1
DAYS MIN <= 0 0 0.5 -0.5
PRECIPITATION (INCHES)
RECORD
MAXIMUM 13.61 1997
MINIMUM 0.49 1983
TOTALS 10.61 6.53 4.08
DAILY AVG. 0.34 0.21 0.13
DAYS >= .01 25 21.1 3.9
DAYS >= .10 20 13.9 6.1
DAYS >= .50 7 4.2 2.8
DAYS >= 1.00 2 1.2 0.8
GREATEST
24 HR. TOTAL 2.01 12/14 TO 12/15
SNOWFALL (INCHES)
RECORDS
TOTAL 54.7
TOTALS 13.2 18.1 -4.9 8.4
SINCE 7/1 19.7 32.8 -13.1
DAYS >= TRACE 18 10.1 7.9 18
DAYS >= 1.0 5 5.0 0.0 2
DEGREE DAYS
HEATING TOTAL 894 1076 -182
SINCE 7/1 3093 3696 -603
COOLING TOTAL 0 0 0
SINCE 1/1 8 2 6
FREEZE DATES
RECORD
EARLIEST 08/24/1969
LATEST 06/13/1965
EARLIEST 10/21
LATEST 05/05
..............................................................
WIND (MPH)
AVERAGE WIND SPEED 10.6
HIGHEST WIND SPEED/DIRECTION 47/110 DATE 12/12
HIGHEST GUST SPEED/DIRECTION 65/110 DATE 12/12
WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM 0 MIXED PRECIP 1
HEAVY RAIN 0 RAIN 9
LIGHT RAIN 27 FREEZING RAIN 0
LT FREEZING RAIN 0 HAIL 0
HEAVY SNOW 0 SNOW 3
LIGHT SNOW 19 SLEET 0
FOG 28 FOG W/VIS <= 1/4 MILE 2
HAZE 0
- INDICATES NEGATIVE NUMBERS.
R INDICATES RECORD WAS SET OR TIED.
MM INDICATES DATA IS MISSING.
T INDICATES TRACE AMOUNT.
$$
...ABOVE NORMAL TEMPERATURES AT THE START OF AN EL NINO WINTER...
Multiple record high temperatures during the month were completely
congruent with a strong El Nino. In fact, Juneau finished the month
nearly 6 degrees above normal for daily average temperatures and a
full 6 inches below normal for snowfall. The remaining climate sites
in Southeast Alaska also recorded 4 to 5 degrees above normal for
their daily average temps. Unfortunately, there is no longer
snowfall information for those locations, but it sure would be nice
to know how they measured when compared to their climate normal
values. While there was a dearth of snow for most of Southeast
Alaska, Skagway and Haines and the associated highways got quite a
bit of it. 4 separate winter storm warnings were issued for these
locations with all of them verifying. One event even included an
avalanche near Klukwan that was captured in a photograph.
A quick glance at the daily data for all 4 climate sites indicates
that the above normal monthly temps was more a result of daytime
highs rather than overnight lows. This departs from the typical
trend we have observed for many months where overnight lows were
more responsible for the warmer than normal temperatures.
In keeping with the trend from this Autumn, all 4 sites finished the
month with significantly above normal precipitation and Sitka nearly
achieving record precipitation for December. There is an established
and well studied connection between above normal normal temperatures
and the strong El Nino. Recent studies are hinting at a similar
relationship regarding precipitation too.
The month also saw a series of strong Autumn storms which, in
addition to producing heavy rain, resulted in high winds across much
of the Panhandle and northeast gulf coast. At various times during
the month, high wind warnings were issued for Yakutat, Skagway,
Juneau, Sitka, Prince of Wales Island, Ketchikan, and Metlakatla.
Fritsch
$$