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000
CXUS55 KRIW 021637
CLMGEY

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

...PRELIMINARY MONTHLY CLIMATE SUMMARY FOR GREYBULL 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

...GREYBULL WAS WARMER AND WETTER THAN NORMAL IN SEPTEMBER...

THE AVERAGE TEMPERATURE FOR GREYBULL IN SEPTEMBER WAS 64 DEGREES
WHICH WAS 3.1 DEGREES ABOVE NORMAL. IT WAS THE 5TH WARMEST SEPTEMBER
ON RECORD. THE WARMEST READING FOR THE MONTH WAS 94 DEGREES ON THE
1ST. THE COLDEST TEMPERATURE WAS 40 DEGREES ON THE 24TH, 25TH, 29TH
AND 30TH. NO TEMPERATURE RECORDS WERE BROKEN.

PRECIPITATION FOR THE MONTH WAS 1.58 INCHES...WHICH IS 190 PERCENT
OF NORMAL. IT WAS THE 4TH WETTEST SEPTEMBER ON RECORD. THE WETTEST
24-HOUR PERIOD OCCURRED ON THE 4TH WITH 0.86 INCHES. THIS BROKE THE
2016 RECORD OF 0.20. THE 22ND HAD 0.31 INCHES AND BROKE THE 2016
RECORD OF 0.25. THE HIGHEST WIND GUST WAS 50 MPH FROM THE NORTHWEST
ON THE 18TH.

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

CLIMATE NORMAL PERIOD: 1991 TO 2020
CLIMATE RECORD PERIOD: 1998 TO 2023

WEATHER         OBSERVED          NORMAL  DEPART   LAST YEAR`S
                VALUE   DATE(S)   VALUE   FROM     VALUE
                                          NORMAL
..............................................................
TEMPERATURE (F)
RECORD
 HIGH            103   09/04/2022
 LOW              27   09/18/2003
                       09/29/1999
HIGHEST           94   09/01
LOWEST            40   09/25
                       09/29
                       09/30
AVG. MAXIMUM    79.8               76.7     3.1
AVG. MINIMUM    48.2               45.1     3.1
MEAN            64.0               60.9     3.1
DAYS MAX >= 90     3
DAYS MAX <= 32     0
DAYS MIN <= 32     0
DAYS MIN <= 0      0

PRECIPITATION (INCHES)
RECORD
 MAXIMUM        3.21   2019
 MINIMUM        0.01   2021
TOTALS          1.58               0.83    0.75     1.16
DAILY AVG.      0.05               0.03    0.02
DAYS >= .01        7
DAYS >= .10        3
DAYS >= .50        1
DAYS >= 1.00       0
GREATEST
 24 HR. TOTAL   0.86   09/04 TO 09/04
 STORM TOTAL    0.86

DEGREE DAYS
HEATING TOTAL     69                169    -100
 SINCE 7/1        74                189    -115
COOLING TOTAL     50                 46       4
 SINCE 1/1       702                742     -40
..............................................................

WIND (MPH)
AVERAGE WIND SPEED              5.6
RESULTANT WIND SPEED/DIRECTION   1/320
HIGHEST WIND SPEED/DIRECTION    36/300    DATE  09/18
HIGHEST GUST SPEED/DIRECTION    50/300    DATE  09/18

SKY COVER
POSSIBLE SUNSHINE (PERCENT)   MM
AVERAGE SKY COVER           0.16
NUMBER OF DAYS FAIR           27
NUMBER OF DAYS PC              2
NUMBER OF DAYS CLOUDY          1

AVERAGE RH (PERCENT)     53

WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM              4     MIXED PRECIP               0
HEAVY RAIN                1     RAIN                       4
LIGHT RAIN               12     FREEZING RAIN              0
LT FREEZING RAIN          0     HAIL                       0
HEAVY SNOW                0     SNOW                       0
LIGHT SNOW                0     SLEET                      0
FOG                       7     FOG W/VIS <= 1/4 MILE      1
HAZE                      1

-  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 68 DEGREES...AND THE AVERAGE LOW TEMPERATURE
IS 39 DEGREES. THE AVERAGE HIGH BY THE END OF THE MONTH IS 52
DEGREES...AND THE AVERAGE LOW TEMPERATURE IS 26 DEGREES. THE AVERAGE
MONTHLY PRECIPITATION IS 0.60 INCHES.

$$