Climatological Report (Monthly)
Issued by NWS Portland, ME
Issued by NWS Portland, ME
270 CXUS51 KGYX 021917 CLMPWM PWMCLMPWM 000 TTAA00 GYX 021757 CLIMATE REPORT NATIONAL WEATHER SERVICE GRAY ME 1257 PM EST TUE JAN 02 2024 ................................... ...THE PORTLAND ME CLIMATE SUMMARY FOR THE MONTH OF DECEMBER 2023... CLIMATE NORMAL PERIOD: 1991 TO 2020 CLIMATE RECORD PERIOD: 1940 TO 2023 (FOR TEMPERATURES) CLIMATE RECORD PERIOD: 1871 TO 2023 (FOR PRECIPITATION) CLIMATE RECORD PERIOD: 1882 TO 2023 (FOR SNOWFALL) WEATHER OBSERVED NORMAL DEPART LAST YEAR`S VALUE DATE(S) VALUE FROM VALUE DATE(S) NORMAL ................................................................ TEMPERATURE (F) RECORD HIGH 71 12/06/2001 12/07/1998 LOW -21 12/31/1963 HIGHEST 59 12/18 56 3 54 12/03 12/23 LOWEST 13 12/07 2 11 12 12/25 AVG. MAXIMUM 42.4 38.3 4.1 39.5 AVG. MINIMUM 28.1 22.4 5.7 24.4 MEAN 35.2 30.3 4.9 31.9 DAYS MAX >= 90 0 0.0 0.0 0 DAYS MAX <= 32 4 8.4 -4.4 7 DAYS MIN <= 32 20 26.7 -6.7 26 DAYS MIN <= 0 0 0.4 -0.4 0 PRECIPITATION (INCHES) RECORD MAXIMUM 9.69 1969 MINIMUM 0.93 1874 TOTALS 6.67 4.50 2.17 3.98 DAILY AVG. 0.22 0.15 0.07 0.13 DAYS >= .01 12 12.3 -0.3 11 DAYS >= .10 8 7.9 0.1 5 DAYS >= .50 5 2.9 2.1 3 DAYS >= 1.00 3 1.3 1.7 3 GREATEST 24 HR. TOTAL 2.47 12/10 TO 12/11 SNOWFALL (INCHES) RECORDS TOTAL 54.8 1970 TOTALS 0.5 14.6 -14.1 4.7 SINCE 7/1 0.7 17.1 -16.4 4.7 SNOWDEPTH AVG. T DAYS >= TRACE 4 6.0 -2.0 DAYS >= 1.0 0 3.3 -3.3 GREATEST SNOW DEPTH T 24 HR TOTAL 0.5 12/04 TO 12/05 DEGREE DAYS HEATING TOTAL 913 1074 -161 1016 SINCE 7/1 2182 2451 -269 2252 COOLING TOTAL 0 0 0 0 SINCE 1/1 423 446 -23 542 ................................................................ WIND (MPH) AVERAGE WIND SPEED 6.5 HIGHEST WIND SPEED/DIRECTION 40/150 DATE 12/18 HIGHEST GUST SPEED/DIRECTION 59/160 DATE 12/18 SKY COVER AVERAGE SKY COVER 0.62 AVERAGE RH (PERCENT) 79 WEATHER CONDITIONS. NUMBER OF DAYS WITH THUNDERSTORM 0 HEAVY RAIN 4 RAIN 6 LIGHT RAIN 13 FREEZING RAIN 0 LT FREEZING RAIN 0 HEAVY SNOW 0 SNOW 0 LIGHT SNOW 3 FOG 16 FOG W/VIS <= 1/4 MILE 4 HAZE 1 - INDICATES NEGATIVE NUMBERS. R INDICATES RECORD WAS SET OR TIED. MM INDICATES DATA IS MISSING. T INDICATES TRACE AMOUNT. && DECEMBER WAS A MILD AND WET MONTH IN THE PORTLAND AREA. THE MONTH STARTED OFF WITH A FRONTAL BOUNDARY NORTH OF NEW ENGLAND THAT SHIFTED SOUTH BETWEEN THE 3RD AND 5TH OF THE MONTH. WAVES OF LOW PRESSURE TRACKED ALONG THIS FRONT THAT BROUGHT THE ONLY MEASURABLE SNOWFALL TO PORTLAND WHEN 0.5 INCHES WAS RECORDED BETWEEN THE 4TH AND 5TH. A BRIEF PERIOD OF BELOW NORMAL TEMPERATURES FOLLOWED BEFORE AN AREA OF LOW PRESSURE TRACKED OVER WESTERN NEW ENGLAND THE 10TH INTO THE 11TH. THIS SYSTEM BROUGHT HEAVY RAIN TO MUCH OF MAINE WITH PORTLAND RECEIVING 2.47 INCHES FROM THIS SYSTEM. ANOTHER STRONG LOW PRESSURE SYSTEM IMPACTED NEW ENGLAND ON THE 17TH AND THE 18TH WHEN IT TRACKED FROM THE EAST COAST OF FLORIDA NORTHWARD THROUGH UPSTATE NEW YORK. THIS SYSTEM BROUGHT SIGNIFICANT RAINFALL TO THE REGION WITH CATASTROPHIC FLOODING IN THE MOUNTAINS AND FOOTHILLS ALONG WITH DAMAGING SOUTHEAST WINDS. PORTLAND RECEIVED 2.32 INCHES OF RAINFALL AND A PEAK WIND GUST OF 59 MPH FROM THIS SYSTEM. QUIET WEATHER FOLLOWED UP UNTIL THE 23RD WHEN A DREARY WEATHER PATTERN SET IN OVER CHRISTMAS WEEKEND THAT PERSISTED UNTIL THE END OF THE MONTH. THE AVERAGE TEMPERATURE FOR THE MONTH WAS 35.2 DEGREES, WHICH WAS 4.9 DEGREES ABOVE NORMAL AND THE SECOND WARMEST DECEMBER ON RECORD. THE WARMEST DECEMBER ON RECORD WAS IN 2015 WHEN THE AVERAGE TEMPERATURE WAS 37.9 DEGREES. THE COOLEST WAS 14.0 DEGREES IN 1989. THE FOLLOWING TABLE LISTS THE WARMEST DECEMBERS ON RECORD. WARMEST AVERAGE TEMPERATURE IN DECEMBER (SINCE 1940)... RANK TEMP YEAR 1 37.9 2015 2 35.2 2023 <=== 3 34.8 2001 4 34.5 2006 34.5 1996 6 33.7 2014 7 33.6 1990 8 33.5 1973 9 33.3 2011 10 33.0 1953 A TOTAL OF 6.67 INCHES OF PRECIPITATION FELL, WHICH WAS 2.17 INCHES ABOVE NORMAL. THE HEAVIEST PRECIPITATION FELL ON THE 10TH INTO THE 11TH WHEN 2.47 INCHES OF RAIN WAS MEASURED. THE WETTEST DECEMBER ON RECORD WAS IN 1969 WHEN 9.69 INCHES FELL. THE DRIEST WAS 0.93 INCHES IN 1874. ONLY 0.5 INCHES OF SNOW FELL, WHICH WAS 14.1 INCHES BELOW NORMAL AND THE 2ND LEAST SNOWY DECEMBER ON RECORD. THE LEAST SNOWY DECEMBER ON RECORD WAS IN 1999 WHEN ONLY A TRACE WAS RECORDED. THE SNOWIEST WAS IN 1970 WHEN 54.8 INCHES FELL. THE FOLLOWING DAILY RECORDS WERE SET OR TIED IN DECEMBER 2023... DATE RECORD PREVIOUS DEC 4 2 - SMALLEST TEMPERATURE RANGE 6 IN 2005 DEC 11 1.99 - GREATEST PRECIPITATION 1.27 IN 1969 DEC 18 59 - WARMEST HIGH TEMPERATURE 53 IN 1996 DEC 18 46 - WARMEST LOW TEMPERATURE 39 IN 1996 DEC 18 53 - WARMEST AVERAGE TEMPERATURE 46 IN 1996 DEC 28 37 - WARMEST LOW TEMPERATURE 37 IN 2014, 2008 (TIED) DEC 28 3 - SMALLEST TEMPERATURE RANGE 4 IN 1940 DEC 29 3 - SMALLEST TEMPERATURE RANGE 4 IN 1959 AND 1942 $$ DS