927
CXAK57 PAJK 042029
CLMKTN
NATIONAL WEATHER SERVICE JUNEAU AK
1121 AM AKST THU JAN 04 2024

...................................

...THE KETCHIKAN CLIMATE SUMMARY FOR THE MONTH OF DECEMBER 2023...

CLIMATE NORMAL PERIOD: 1991 TO 2020
CLIMATE RECORD PERIOD: 1910 TO 2024

WEATHER         OBSERVED          NORMAL  DEPART   LAST YEAR`S
                VALUE   DATE(S)   VALUE   FROM     VALUE
                                          NORMAL
..............................................................
TEMPERATURE (F)
RECORD
 HIGH             62   12/12/1962
 LOW              -1   12/15/1964
HIGHEST           53   12/29         51       2
LOWEST            29   12/15         17      12
                       12/16
AVG. MAXIMUM    45.0               40.2     4.8
AVG. MINIMUM    37.1               32.6     4.5
MEAN            41.0               36.4     4.6
DAYS MAX >= 90     0                0.0     0.0
DAYS MAX <= 32     0                3.0    -3.0
DAYS MIN <= 32     5               14.4    -9.4
DAYS MIN <= 0      0                0.0     0.0

PRECIPITATION (INCHES)
RECORD
 MAXIMUM       35.16   1930
 MINIMUM        2.01   2021
TOTALS         22.45              16.27    6.18
DAILY AVG.      0.72               0.52    0.20
DAYS >= .01       30               22.4     7.6
DAYS >= .10       26               17.7     8.3
DAYS >= .50       16               10.4     5.6
DAYS >= 1.00       7                5.7     1.3
GREATEST
 24 HR. TOTAL   3.59   12/25 TO 12/26


DEGREE DAYS
HEATING TOTAL    738                887    -149
 SINCE 7/1      2429               2962    -533
COOLING TOTAL      0                  0       0
 SINCE 1/1        25                 16       9

FREEZE DATES
EARLIEST                        10/23
LATEST                          04/19
..............................................................

WIND (MPH)
AVERAGE WIND SPEED              10.5
HIGHEST WIND SPEED/DIRECTION    40/140    DATE  12/12
HIGHEST GUST SPEED/DIRECTION    62/130    DATE  12/12


WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM              0     MIXED PRECIP               0
HEAVY RAIN                6     RAIN                      20
LIGHT RAIN               30     FREEZING RAIN              0
LT FREEZING RAIN          0     HAIL                       0
HEAVY SNOW                0     SNOW                       0
LIGHT SNOW                1     SLEET                      0
FOG                      28     FOG W/VIS <= 1/4 MILE      0
HAZE                      1

-  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
$$