Climatological Report (Monthly)
Issued by NWS Juneau, AK
Issued by NWS Juneau, AK
711 CXAK57 PAJK 030124 CLMAJK NATIONAL WEATHER SERVICE JUNEAU AK 358 PM AKST FRI FEB 02 2024 ................................... ...THE JUNEAU CLIMATE SUMMARY FOR THE MONTH OF JANUARY 2024... 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 60 01/20/1942 LOW -22 01/12/1972 HIGHEST 48 01/29 43 5 LOWEST 2 01/12 2 0 AVG. MAXIMUM 32.4 33.1 -0.7 AVG. MINIMUM 23.8 23.8 0.0 MEAN 28.1 28.5 -0.4 DAYS MAX >= 90 0 0.0 0.0 DAYS MAX <= 32 14 12.0 2.0 DAYS MIN <= 32 27 22.7 4.3 DAYS MIN <= 0 0 0.9 -0.9 PRECIPITATION (INCHES) RECORD MAXIMUM 12.29 2022 MINIMUM 0.94 1969 TOTALS 9.68 6.02 3.66 DAILY AVG. 0.31 0.19 0.12 DAYS >= .01 21 20.4 0.6 DAYS >= .10 16 13.4 2.6 DAYS >= .50 6 3.9 2.1 DAYS >= 1.00 3 1.1 1.9 GREATEST 24 HR. TOTAL 1.84 01/29 TO 01/29 SNOWFALL (INCHES) RECORDS TOTAL 75.2 TOTALS 76.8R 24.5 52.3 5.7 SINCE 7/1 96.5 57.3 39.2 DAYS >= TRACE 17 10.3 6.7 11 DAYS >= 1.0 11 6.2 4.8 3 DEGREE DAYS HEATING TOTAL 1135 1133 2 SINCE 7/1 4228 4831 -603 COOLING TOTAL 0 0 0 SINCE 1/1 0 0 0 FREEZE DATES RECORD EARLIEST 08/24/1969 LATEST 06/13/1965 EARLIEST 10/21 LATEST 05/05 .............................................................. WIND (MPH) AVERAGE WIND SPEED 7.2 HIGHEST WIND SPEED/DIRECTION 40/110 DATE 01/29 HIGHEST GUST SPEED/DIRECTION 57/120 DATE 01/29 WEATHER CONDITIONS. NUMBER OF DAYS WITH THUNDERSTORM 0 MIXED PRECIP 1 HEAVY RAIN 0 RAIN 2 LIGHT RAIN 12 FREEZING RAIN 0 LT FREEZING RAIN 4 HAIL 0 HEAVY SNOW 0 SNOW 5 LIGHT SNOW 17 SLEET 0 FOG 24 FOG W/VIS <= 1/4 MILE 6 HAZE 0 - INDICATES NEGATIVE NUMBERS. R INDICATES RECORD WAS SET OR TIED. MM INDICATES DATA IS MISSING. T INDICATES TRACE AMOUNT. $$ ...EL NINO WINTER OR NOT, JANUARY WAS COLDER THAN NORMAL WITH OVER 3 TIMES THE NORMAL JANUARY SNOWFALL IN SOME LOCATIONS... The middle of the month saw a multi-day snow event from 12 to 15 January. The setup featured very cold surface airmass with widespread temperatures in the single digits or, in some cases below zero Farehheit. The moisture laden weather system moved in and produced heavy snow over many locations. In Juneau, the 3-day snow total at the airport was 28.3 inches, which was 4th place for a 3- day event in the month of January and 15th place overall for any month. Other notable facts: Juneau reached its month normal snowfall for January before the middle of the month during this event. Additionally, snow ratios for Southeast Alaska are typically 5:1 or 10:1, meaning that 5 (or 10) inches of snow equates to 1 inch of liquid water. At the beginning of this event while temperatures were still bitterly cold, the snow ratio at the forecast office in Juneau was a phenomenal 55:1 - thats 55 inches of snow for every 1 inch of liquid. What do you think about THAT, NWS Boulder! One week later, beginning on the 21st of January, Southeast Alaska experienced another multi-day snow event. By the end of the 24th of January, Juneau recorded another 35.3 inches of snow and snow depth at the airport maxed out at 38 inches. In the back of the Mendenhall Valley, the forecast office recorded 30.9 inches of new snow with a maximum depth of 40 inches at midnight on the 24th. The main difference between these two snow events had to do with the very different snow ratios. While the first event featured very light and fluffy powder that could be easily cleared of driveways and side walks with a household leaf blower, the water content of that snow was relatively little. The second event featured much lower snow ratios and higher liquid water equivalent, which made snow and berm removal much more difficult. With over 3 feet of snow on the ground (and rooftops) after the second snow event, temperatures began warming to above normal temperatures with overnight lows above freezing for the last week of the month. Additionally, a significant abount of rain fell on the snowpack, causing the snow water equivalent, or SWE to rise to over 6 inches, meaning that horizontal surfaces were bearing a snow load of over 30 pounds persquare foot. Fortunately, very few collapsed roofs were reported and numerous residents took the proactive measure of cleaning their roofs "just in case". By the end of the month, SWE and snow loading on roofs was no longer a concern, as the rain of the last few days had eliminated much of the snow pack and most of the rooftop snow. All just in time for a third round of significant snowfall that began on the evening of the 31st of January. By midnight, 6.8 inches of new snow had fallen at the Juneau airport, raising the January monthly total to 76.8 inches and claiming the title as snowiest January on record. This was also the second snowiest of any month on record. Fritsch $$