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000
CXUS51 KLWX 011451
CLMIAD

CLIMATE REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1051 AM EDT FRI OCT 01 2021

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

...THE WASHINGTON DULLES DC CLIMATE SUMMARY FOR THE MONTH OF SEPTEMBER 2021...

CLIMATE NORMAL PERIOD: 1991 TO 2020
CLIMATE RECORD PERIOD: 1960 TO 2021

WEATHER         OBSERVED          NORMAL  DEPART   LAST YEAR`S
                VALUE   DATE(S)   VALUE   FROM     VALUE
                                          NORMAL
..............................................................
TEMPERATURE (F)
RECORD
 HIGH             99   09/11/1983
                       09/10/1983
                       09/02/1980
 LOW              30   09/24/1974
HIGHEST           89   09/08         91      -2       91
                       09/14
                       09/15
LOWEST            45   09/30         39       6       38
AVG. MAXIMUM    80.8               79.3     1.5     77.3
AVG. MINIMUM    59.1               57.9     1.2     57.1
MEAN            69.9               68.6     1.3     67.2
DAYS MAX >= 90     0                3.1    -3.1        1
DAYS MAX <= 32     0                0.0     0.0        0
DAYS MIN <= 32     0                0.0     0.0        0
DAYS MIN <= 0      0                0.0     0.0        0

PRECIPITATION (INCHES)
RECORD
 MAXIMUM       11.26   1975
 MINIMUM        0.15   2005
TOTALS          4.72               3.94    0.78     2.28
DAILY AVG.      0.16               0.13    0.03     0.08
DAYS >= .01        8                9.0    -1.0       11
DAYS >= .10        5                5.9    -0.9        8
DAYS >= .50        3                2.5     0.5        1
DAYS >= 1.00       2                1.2     0.8        0
GREATEST
 24 HR. TOTAL   1.95   08/31 TO 09/01               0.88
 STORM TOTAL    1.93                                0.77
 (MM/DD(HH))

SNOWFALL (INCHES)
RECORDS
 TOTAL            MM   MM
TOTALS           0.0                0.0     0.0      0.0
SINCE 7/1        0.0                0.0     0.0       MM
DAYS >= TRACE      0                0.0     0.0        0
DAYS >= 1.0        0                0.0     0.0        0
GREATEST
 SNOW DEPTH        0                                   0

DEGREE DAYS
HEATING TOTAL     17                 45     -28       61
 SINCE 7/1        17                 44     -27       MM
COOLING TOTAL    171                152      19      135
 SINCE 1/1      1423               1208     215       MM
..............................................................

WIND (MPH)
AVERAGE WIND SPEED              5.9
HIGHEST WIND SPEED/DIRECTION    24/150
HIGHEST GUST SPEED/DIRECTION    37/160

SKY COVER
AVERAGE SKY COVER           0.44

AVERAGE RH (PERCENT)     71

WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM              7     MIXED PRECIP               0
HEAVY RAIN                3     RAIN                       6
LIGHT RAIN               10     FREEZING RAIN              0
LT FREEZING RAIN          0     HAIL                       0
HEAVY SNOW                0     SNOW                       0
LIGHT SNOW                0     SLEET                      0
FOG                      11     FOG W/VIS <= 1/4 MILE      0
HAZE                      0

-  INDICATES NEGATIVE NUMBERS.
R  INDICATES RECORD WAS SET OR TIED.
MM INDICATES DATA IS MISSING.
T  INDICATES TRACE AMOUNT.

&&

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

WASHINGTON DULLES INTERNATIONAL AIRPORT...

THE AVERAGE TEMPERATURE IN SEPTEMBER 2021 WAS ABOVE NORMAL. IT WAS
THE WARMEST SEPTEMBER SINCE 2019, WHEN THE AVERAGE TEMPERATURE WAS
72.5 DEGREES.

TOTAL PRECIPITATION WAS 120 PERCENT OF NORMAL. IT WAS THE WETTEST
SEPTEMBER SINCE 2018, WHEN 7.36 INCHES OF PRECIPITATION FELL.

A RECORD WARM LOW TEMPERATURE WAS SET ON SEPTEMBER 16TH WHEN THE LOW
WAS ONLY 69 DEGREES. THIS TIED THE RECORD LAST SET IN 2005.

WEATHER RECORDS FOR THE DULLES VA AREA HAVE BEEN RECORDED AT WHAT IS
NOW WASHINGTON DULLES INTERNATIONAL AIRPORT SINCE 1960. THE OFFICIAL
RECORD CONSISTS SOLELY OF DATA RECORDED AT THE AIRPORT. TEMPERATURE
AND PRECIPITATION RECORDS BEGAN IN 1960. SNOWFALL RECORDS BEGAN IN
1962.

ALL CLIMATE DATA ARE CONSIDERED PRELIMINARY UNTIL REVIEWED BY THE
NATIONAL CENTERS FOR ENVIRONMENTAL INFORMATION (NCEI).

$$

RCM