Climatological Report (Monthly)
Issued by NWS
Issued by NWS
000 CXAK57 PAJK 021856 CLMASI NATIONAL WEATHER SERVICE JUNEAU AK 1047 AM AKDT SAT SEP 02 2023 ................................... ...THE SITKA CLIMATE SUMMARY FOR THE MONTH OF AUGUST 2023... CLIMATE NORMAL PERIOD: 1991 TO 2020 CLIMATE RECORD PERIOD: 1944 TO 2023 WEATHER OBSERVED NORMAL DEPART LAST YEAR`S VALUE DATE(S) VALUE FROM VALUE NORMAL .............................................................. TEMPERATURE (F) RECORD HIGH 84 08/18/1950 LOW 34 08/15/1945 HIGHEST 73 08/27 72 1 LOWEST 51 08/21 46 5 AVG. MAXIMUM 64.5 61.8 2.7 AVG. MINIMUM 56.7 52.9 3.8 MEAN 60.6 57.3 3.3 DAYS MAX >= 90 0 0.0 0.0 DAYS MAX <= 32 0 0.0 0.0 DAYS MIN <= 32 0 0.0 0.0 DAYS MIN <= 0 0 0.0 0.0 PRECIPITATION (INCHES) RECORD MAXIMUM 19.51 1961 MINIMUM 1.62 2019 TOTALS 8.27 7.25 1.02 DAILY AVG. 0.27 0.23 0.04 DAYS >= .01 19 19.4 -0.4 DAYS >= .10 14 13.3 0.7 DAYS >= .50 2 5.2 -3.2 DAYS >= 1.00 1 1.7 -0.7 GREATEST 24 HR. TOTAL 4.43 08/11 TO 08/12 DEGREE DAYS HEATING TOTAL 130 238 -108 SINCE 7/1 298 502 -204 COOLING TOTAL 1 1 0 SINCE 1/1 2 1 1 FREEZE DATES EARLIEST 10/08 LATEST 03/14 .............................................................. WIND (MPH) AVERAGE WIND SPEED 6.1 HIGHEST WIND SPEED/DIRECTION 24/170 DATE 08/12 24/110 08/14 HIGHEST GUST SPEED/DIRECTION 31/150 DATE 08/12 31/190 08/15 WEATHER CONDITIONS. NUMBER OF DAYS WITH THUNDERSTORM 0 MIXED PRECIP 0 HEAVY RAIN 4 RAIN 8 LIGHT RAIN 22 FREEZING RAIN 0 LT FREEZING RAIN 0 HAIL 0 HEAVY SNOW 0 SNOW 0 LIGHT SNOW 0 SLEET 0 FOG 22 FOG W/VIS <= 1/4 MILE 0 HAZE 13 - INDICATES NEGATIVE NUMBERS. R INDICATES RECORD WAS SET OR TIED. MM INDICATES DATA IS MISSING. T INDICATES TRACE AMOUNT. $$ ...EXCELLENT SUMMER WEATHER CONTINUES FOR SOUTHEAST ALASKA IN AUGUST IN ADDITION TO MASSIVE FLOODING ALONG THE MENDENHALL RIVER... The bigest news of the month was the record flooding on the Medenhall River near Juneau that occurred on the 5th and 6th of August. At that time, the glacially dammed lake known as Suicide Basin broke and allowed multi-billion gallons of water to escape underneath the glacier and empty into Mendenhall Lake. Leading up to this flooding event, the basin had filled steadily over the past several months from a combination of snow melt, ice melt, and runoff from periodic bouts of rainfall through the season. The release occurred later in the Summer than average, which allowed it to fill higher than usual. Water overtopped the glacier for a few days before the big release. The release occurred rather quickly with the majority of the flooding along the Mendenhall River occurring within a 24-hour period. The gauge on Mendenhall Lake broke its previous depth record by nearly 3 feet with a crest of 14.97 ft slightly before midnight on the 5th of August. The previous record was 11.99 ft, which was set during the 2016 release. This record-breaking event caused many homes, roads, and the Skater`s Cabin campground to flood. The high water and the force of the water also prompted the closure of the bridge over the river on Back Loop Road. The erosion of the meandering riverbanks also resulted in the direct loss of 2 homes and the condemmnation of multipe structures due to undermining of their foundations. In other monthly climate news, at a time of the year when precipitation is on the rise across Southeast Alaska, there were a good number of days with sunny skies & dry conditions which kept temperatures above average for the month for all 4 climate sites. Most days were dominated by a ridge of high pressure, which kept much of the region under decreased cloudiness and drier conditions and resulted in below normal rainfall totals for most, but not, all locations. One of the exceptions was Sitka. The central outer coast experienced above normal rainfall for the month, primarily due to receiving heavier and more plentiful shower activity from topographic enhancement from more abundant onshore-flow for the month. Regarding records for August, Juneau Airport received 0.94" of rainfall on the 1st , which exceeded the previous record of 0.84", which was set back in 1970. Juneau Airport also set a new record high of 81 degrees on August 6th, which broke the old record of 78, which was set back in 2017. On the 7th, Ketchikan set a new rainfall record of 3.18", which exceeded the old record there of 2.33" set back in 2006. On the 12th, Sitka recorded 4.42" of rainfall, which broke the old record of 4.22" set back in 1961. Finally, on the 27th, Sitka tied the old high temperature record of 73, set back in 1966. Chambers/Fritsch $$