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000
CXUS55 KRIW 021635
CLMCPR

CLIMATE REPORT
NATIONAL WEATHER SERVICE RIVERTON WY
1021 AM MDT MON OCT 02 2023

...PRELIMINARY MONTHLY CLIMATE SUMMARY FOR CASPER FOR THE MONTH OF
SEPTEMBER 2023...

...OFFICIAL CLIMATE DATA FOR THE MONTH OF SEPTEMBER 2023 WILL BE
AVAILABLE IN APPROXIMATELY 60 DAYS FROM THE NATIONAL CENTERS FOR
ENVIRONMENTAL INFORMATION (HTTP://WWW.NCDC.NOAA.GOV/CDO-
WEB/DATASETS). UNOFFICIAL ASOS DAILY SUMMARIES ARE AVAILABLE ON THE
INTERNET AT HTTP://WWW.WEATHER.GOV/CLIMATE/INDEX.PHP?WFO=RIW

...SEPTEMBER WAS DRIER AND WARMER THAN NORMAL FOR CASPER...

THE AVERAGE TEMPERATURE FOR CASPER IN SEPTEMBER WAS 61.2 DEGREES
WHICH WAS 2.3 DEGREES ABOVE NORMAL. THE WARMEST READING FOR THE
MONTH WAS 91 DEGREES ON THE 1ST. THE COLDEST TEMPERATURE WAS 33
DEGREES ON THE 26TH. NO TEMPERATURE RECORDS WERE BROKEN.

PRECIPITATION FOR THE MONTH WAS 0.59 INCHES...WHICH IS 62 PERCENT OF
NORMAL. THE WETTEST 24-HOUR PERIOD WAS ON THE 14TH WHEN 0.23 INCHES
FELL. NO PRECIPITATION RECORDS WERE BROKEN. THE HIGHEST WIND GUST
WAS 56 MPH FROM THE SOUTHWEST ON THE 4TH.

...THE CASPER WY CLIMATE SUMMARY FOR THE MONTH OF SEPTEMBER 2023...

CLIMATE NORMAL PERIOD: 1991 TO 2020
CLIMATE RECORD PERIOD: 1939 TO 2023

WEATHER         OBSERVED          NORMAL  DEPART   LAST YEAR`S
                VALUE   DATE(S)   VALUE   FROM     VALUE
                                          NORMAL
..............................................................
TEMPERATURE (F)
RECORD
 HIGH            100   09/04/2022
 LOW              15   09/28/1945
HIGHEST           91   09/01
LOWEST            33   09/26
AVG. MAXIMUM    78.9               75.6     3.3
AVG. MINIMUM    43.5               42.2     1.3
MEAN            61.2               58.9     2.3
DAYS MAX >= 90     1
DAYS MAX <= 32     0
DAYS MIN <= 32     0
DAYS MIN <= 0      0

PRECIPITATION (INCHES)
RECORD
 MAXIMUM        3.40   1982
 MINIMUM        0.07   1956
TOTALS          0.59               0.95   -0.36     0.81
DAILY AVG.      0.02               0.03   -0.01
DAYS >= .01        7
DAYS >= .10        2
DAYS >= .50        0
DAYS >= 1.00       0
GREATEST
 24 HR. TOTAL   0.23   09/14 TO 09/14
 STORM TOTAL    0.23

SNOWFALL (INCHES)
TOTALS           0.0                1.5    -1.5
SINCE 7/1        0.0                1.5    -1.5
SNOWDEPTH AVG.     0
DAYS >= 1.0        0

DEGREE DAYS
HEATING TOTAL    127                214     -87
 SINCE 7/1       180                258     -78
COOLING TOTAL     20                 30     -10
 SINCE 1/1       342                442    -100
..............................................................

WIND (MPH)
AVERAGE WIND SPEED              9.4
RESULTANT WIND SPEED/DIRECTION   4/240
HIGHEST WIND SPEED/DIRECTION    40/230    DATE  09/04
HIGHEST GUST SPEED/DIRECTION    56/230    DATE  09/04

SKY COVER
POSSIBLE SUNSHINE (PERCENT)   MM
AVERAGE SKY COVER           0.18
NUMBER OF DAYS FAIR           24
NUMBER OF DAYS PC              6
NUMBER OF DAYS CLOUDY          0

AVERAGE RH (PERCENT)     52

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

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

LOOKING AHEAD TO OCTOBER 2023...THE AVERAGE HIGH TEMPERATURE ON THE
FIRST OF THE MONTH IS 67 DEGREES...AND THE AVERAGE LOW TEMPERATURE
IS 36 DEGREES. THE AVERAGE HIGH BY THE END OF THE MONTH IS 53
DEGREES...AND THE AVERAGE LOW TEMPERATURE IS 26. THE AVERAGE MONTHLY
PRECIPITATION IS 1.19 INCHES. THE AVERAGE MONTHLY SNOWFALL IS 7
INCHES.

$$