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000
CXUS51 KLWX 030002
CLMIAD

CLIMATE REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
802 PM EDT MON OCT 02 2023

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

...THE WASHINGTON DULLES DC CLIMATE SUMMARY FOR THE MONTH OF SEPTEMBER 2023...

CLIMATE NORMAL PERIOD: 1991 TO 2020
CLIMATE RECORD PERIOD: 1960 TO 2023

WEATHER         OBSERVED          NORMAL  DEPART   LAST YEAR`S
                VALUE   DATE(S)   VALUE   FROM     VALUE
                                          NORMAL
..............................................................
TEMPERATURE (F)
RECORD
 HIGH            100   09/06/2023
 LOW              30   09/24/1974
HIGHEST          100R  09/06         91       9       90
LOWEST            49   09/16         39      10       41
                       09/20
AVG. MAXIMUM    82.1               79.3     2.8     80.2
AVG. MINIMUM    60.6               57.9     2.7     58.5
MEAN            71.3               68.6     2.8     69.3
DAYS MAX >= 90     9                3.1     5.9        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          6.65               3.94    2.71     3.28
DAILY AVG.      0.22               0.13    0.09     0.11
DAYS >= .01       13                9.0     4.0        8
DAYS >= .10        8                5.9     2.1        6
DAYS >= .50        5                2.5     2.5        3
DAYS >= 1.00       3                1.2     1.8        1
GREATEST
 24 HR. TOTAL   2.25   09/23 TO 09/24               1.29
 STORM TOTAL    1.51                                1.17
 (MM/DD(HH))

SNOWFALL (INCHES)
RECORDS
 TOTAL            MM   MM
TOTALS             T                0.0     0.0      0.0
SINCE 7/1          T                0.0     0.0       MM
DAYS >= TRACE      2                0.0     2.0        0
DAYS >= 1.0        0                0.0     0.0        0
GREATEST
 SNOW DEPTH        0                                   0

DEGREE DAYS
HEATING TOTAL     16                 45     -29       39
 SINCE 7/1        16                 44     -28       MM
COOLING TOTAL    216                152      64      176
 SINCE 1/1      1331               1208     123       MM
..............................................................

WIND (MPH)
AVERAGE WIND SPEED              6.4
HIGHEST WIND SPEED/DIRECTION    37/300
HIGHEST GUST SPEED/DIRECTION    49/290

SKY COVER
AVERAGE SKY COVER           0.57

AVERAGE RH (PERCENT)     66

WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM              5     MIXED PRECIP               0
HEAVY RAIN                5     RAIN                       4
LIGHT RAIN               13     FREEZING RAIN              0
LT FREEZING RAIN          0     HAIL                       2
HEAVY SNOW                0     SNOW                       0
LIGHT SNOW                0     SLEET                      0
FOG                      12     FOG W/VIS <= 1/4 MILE      0
HAZE                      6

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

&&

AFTER RECORD HEAT TO BEGIN THE MONTH, SEPTEMBER WOUND UP JUST SHY OF 3
DEGREES ABOVE NORMAL. MULTIPLE THUNDERSTORMS JUST AFTER THE EARLY MONTH
HEAT BROKE HELPED PUSH MONTHLY PRECIPITATION WELL ABOVE NORMAL.

THE HIGH TEMPERATURE OF 100 ON SEPTEMBER 6TH WAS THE HOTTEST TEMPERATURE
EVER RECORDED IN THE MONTH OF SEPTEMBER.

$$

DHOF