Climatological Report (Monthly)
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
000
CXUS55 KRIW 021638
CLMP60

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

...PRELIMINARY MONTHLY CLIMATE SUMMARY FOR LAKE YELLOWSTONE FOR THE
MONTH OF SEPTEMBER 2023...

...OFFICIAL CLIMATE DATA FOR THE MONTH OF SEPTEMBER 2023 WILL BE
AVAILABLE APPROXIMATELY IN 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

...LAKE YELLOWSTONE WAS WARMER AND WETTER IN SEPTEMBER...

AVERAGE TEMPERATURE FOR LAKE YELLOWSTONE IN SEPTEMBER WAS 47.1
DEGREES WHICH IS 1.7 DEGREES ABOVE NORMAL. THE WARMEST READING OF
THE MONTH WAS 71 DEGREES ON THE 1ST. THE COLDEST READING OF THE
MONTH WAS ON THE 29TH  WITH 26 DEGREES. NO TEMPERATURE RECORDS WERE
BROKEN.

TOTAL PRECIPITATION AT LAKE YELLOWSTONE WAS 3.62  INCHES... WHICH
WAS 231 PERCENT OF NORMAL. IT WAS THE 2ND WETTEST SEPTEMBER ON
RECORD. THE WETTEST 24-HOUR PERIOD DURING THE MONTH WAS THE 20TH-
21ST WHEN 1.57 INCHES OF PRECIPITATION FELL. THE 21ST HAD 1.20
INCHES AND BROKE THE 2006 RECORD OF 0.43. THE 3RD HAD 0.84 AND BROKE
THE 2004 RECORD OF 0.29. THE 13TH HAD 0.68 INCHES AND BROKE 0.27
FROM 2017. THE HIGHEST WIND GUST WAS 32 MPH FROM THE SOUTHWEST ON
THE 1ST.

...THE LAKE YELLOWSTONE 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             83   09/07/2022
 LOW              13   09/24/2000
HIGHEST           71   09/01
LOWEST            26   09/29
AVG. MAXIMUM    61.3               60.5     0.8
AVG. MINIMUM    32.9               30.3     2.6
MEAN            47.1               45.4     1.7
DAYS MAX >= 90     0
DAYS MAX <= 32     0
DAYS MIN <= 32    14
DAYS MIN <= 0      0

PRECIPITATION (INCHES)
RECORD
 MAXIMUM        4.09   2013
 MINIMUM        0.21   2018
TOTALS          3.62               1.57    2.05     1.62
DAILY AVG.      0.12               0.05    0.07
DAYS >= .01       10
DAYS >= .10        7
DAYS >= .50        3
DAYS >= 1.00       1
GREATEST
 24 HR. TOTAL   1.57   09/20 TO 09/21
 STORM TOTAL    1.20

DEGREE DAYS
HEATING TOTAL    496                588     -92
 SINCE 7/1      1029               1230    -201
COOLING TOTAL      0                  0       0
 SINCE 1/1         0                  0       0
..............................................................

WIND (MPH)
AVERAGE WIND SPEED              1.9
RESULTANT WIND SPEED/DIRECTION   0/070
HIGHEST WIND SPEED/DIRECTION    17/280    DATE  09/08
HIGHEST GUST SPEED/DIRECTION    32/200    DATE  09/01

SKY COVER
POSSIBLE SUNSHINE (PERCENT)   MM
AVERAGE SKY COVER           0.00
NUMBER OF DAYS FAIR           28
NUMBER OF DAYS PC              0
NUMBER OF DAYS CLOUDY          0

AVERAGE RH (PERCENT)     69

WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM              2     MIXED PRECIP               0
HEAVY RAIN                1     RAIN                       5
LIGHT RAIN               10     FREEZING RAIN              0
LT FREEZING RAIN          0     HAIL                       0
HEAVY SNOW                0     SNOW                       0
LIGHT SNOW                0     SLEET                      0
FOG                       0     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.

LOOKING AHEAD TO OCTOBER 2023...THE AVERAGE HIGH TEMPERATURE ON THE
FIRST OF THE MONTH IS 53 DEGREES...AND THE AVERAGE LOW TEMPERATURE
IS 27 DEGREES. THE AVERAGE HIGH BY THE END OF THE MONTH IS 39
DEGREES AND THE AVERAGE LOW TEMPERATURE IS 17 DEGREES. THE AVERAGE
MONTHLY PRECIPITATION IS 1.85 INCHES.

$$


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.