732
CXUS55 KRIW 011717
CLMLND

CLIMATE REPORT
NATIONAL WEATHER SERVICE RIVERTON WY
1105 AM MDT THU OCT 01 2026

...PRELIMINARY MONTHLY CLIMATE SUMMARY FOR LANDER FOR THE MONTH OF
SEPTEMBER 2026...

...OFFICIAL CLIMATE DATA FOR THE MONTH OF SEPTEMBER 2026 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

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

THE AVERAGE TEMPERATURE FOR LANDER IN SEPTEMBER WAS 63.3 DEGREES
WHICH WAS 3.7 DEGREES ABOVE NORMAL. THE WARMEST READING FOR THE
MONTH WAS 88 DEGREES ON THE 6TH AND 13TH. THE COLDEST TEMPERATURE
WAS 39 DEGREES ON THE 15TH. NO TEMPERATURE RECORDS WERE BROKEN THIS
MONTH.

PRECIPITATION FOR THE MONTH WAS 2.18 INCHES...WHICH IS 222 PERCENT
OF NORMAL. THE WETTEST 24-HOUR PERIOD WAS THE 19TH...WITH 1.64
INCHES OF PRECIPITATION. THIS BROKE THE 1999 RECORD OF 0.72 INCHES.
THE HIGHEST WIND GUST WAS 52 MPH AND OCCURRED ON THE 27TH FROM THE
SOUTHWEST.

...THE LANDER WY CLIMATE SUMMARY FOR THE MONTH OF SEPTEMBER 2026...

CLIMATE NORMAL PERIOD: 1991 TO 2020
CLIMATE RECORD PERIOD: 1891 TO 2026

WEATHER         OBSERVED          NORMAL  DEPART   LAST YEAR`S
                VALUE   DATE(S)   VALUE   FROM     VALUE
                                          NORMAL
..............................................................
TEMPERATURE (F)
RECORD
 HIGH             99   09/04/2022
 LOW               7   09/22/1895
HIGHEST           88   09/05
                       09/06
                       09/13
LOWEST            39   09/15
AVG. MAXIMUM    77.7               74.6     3.1
AVG. MINIMUM    48.8               44.6     4.2
MEAN            63.3               59.6     3.7
DAYS MAX >= 90     0
DAYS MAX <= 32     0
DAYS MIN <= 32     0
DAYS MIN <= 0      0

PRECIPITATION (INCHES)
RECORD
 MAXIMUM        5.64   1923
 MINIMUM           T   2010
TOTALS          2.18               0.98    1.20     1.20
DAILY AVG.      0.07               0.03    0.04
DAYS >= .01        7
DAYS >= .10        3
DAYS >= .50        1
DAYS >= 1.00       1
GREATEST
 24 HR. TOTAL   1.64   09/19 TO 09/19
 STORM TOTAL    1.64

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     89                195    -106
 SINCE 7/1        92                233    -141
COOLING TOTAL     44                 32      12
 SINCE 1/1       714                484     230
..............................................................

WIND (MPH)
AVERAGE WIND SPEED              7.3
RESULTANT WIND SPEED/DIRECTION   3/240
HIGHEST WIND SPEED/DIRECTION    38/230    DATE  09/27
HIGHEST GUST SPEED/DIRECTION    52/230    DATE  09/27

SKY COVER
POSSIBLE SUNSHINE (PERCENT)   MM
AVERAGE SKY COVER           0.14
NUMBER OF DAYS FAIR           27
NUMBER OF DAYS PC              2
NUMBER OF DAYS CLOUDY          1

AVERAGE RH (PERCENT)     44

WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM              4     MIXED PRECIP               0
HEAVY RAIN                1     RAIN                       3
LIGHT RAIN                8     FREEZING RAIN              0
LT FREEZING RAIN          0     HAIL                       0
HEAVY SNOW                0     SNOW                       0
LIGHT SNOW                0     SLEET                      0
FOG                       3     FOG W/VIS <= 1/4 MILE      0
HAZE                      2

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

LOOKING AHEAD TO OCTOBER 2026. THE AVERAGE HIGH TEMPERATURE ON THE
FIRST OF THE MONTH IS 67 DEGREES...AND THE AVERAGE LOW TEMPERATURE
IS 38 DEGREES. THE AVERAGE HIGH BY THE END OF THE MONTH IS 52
DEGREES...AND THE AVERAGE LOW TEMPERATURE IS 26. THE AVERAGE MONTHLY
PRECIPITATION IS 1.40 INCHES. THE AVERAGE MONTHLY SNOWFALL IS 10.5
INCHES.

$$