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CXUS46 KOTX 022339
CLMLWS

CLIMATE REPORT
NATIONAL WEATHER SERVICE SPOKANE WA
438 PM PDT FRI OCT 02 2026

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

...THE LEWISTON ID AIRPORT CLIMATE SUMMARY FOR THE MONTH OF
SEPTEMBER 2026...

CLIMATE NORMAL PERIOD 1991 TO 2020
CLIMATE RECORD PERIOD 1881 TO 2026

WEATHER         OBSERVED          NORMAL  DEPART   LAST YEAR`S
                VALUE   DATE(S)   VALUE   FROM     VALUE DATE(S)
                                          NORMAL
................................................................
TEMPERATURE (F)
RECORD
 HIGH            108   09/06/1944
 LOW              27   09/24/1926
HIGHEST           88   09/10         MM      MM      102  09/01
                                                          09/02
LOWEST            41   09/28         MM      MM       48  09/23
                                                          09/27
AVG. MAXIMUM    74.9               79.5    -4.6     84.8
AVG. MINIMUM    51.6               52.3    -0.7     57.9
MEAN            63.3               65.9    -2.7     71.4
DAYS MAX >= 90     0                4.4    -4.4        8
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        4.37   1940
 MINIMUM           T   2012
TOTALS          1.63               0.60    1.03     1.24
DAILY AVG.      0.05               0.02    0.03     0.04
DAYS >= .01       10                4.7     5.3        9
DAYS >= .10        2                1.8     0.2        3
DAYS >= .50        2                0.2     1.8        1
DAYS >= 1.00       0                0.0     0.0        0
GREATEST
 24 HR. TOTAL   0.74   09/12 TO 09/13               0.53

SNOWFALL (INCHES)
RECORDS
 TOTAL             T   1926
TOTALS           0.0                0.0     0.0      0.0
SINCE 7/1        0.0                0.0     0.0       MM
SNOWDEPTH AVG.     0                                   0
DAYS >= 1.0        0                0.0     0.0        0
GREATEST
 SNOW DEPTH        0                                   0  MM
 24 HR TOTAL      MM                                 0.0

DEGREE DAYS
HEATING TOTAL     86                 76      10       14
 SINCE 7/1        87                 88      -1       MM
COOLING TOTAL     39                102     -63      211
 SINCE 1/1       913                908       5       MM
................................................................

WIND (MPH)
AVERAGE WIND SPEED              4.5
HIGHEST WIND SPEED/DIRECTION    30/300    DATE  09/12
                                30/240          09/25
HIGHEST GUST SPEED/DIRECTION    43/300    DATE  09/12

SKY COVER
POSSIBLE SUNSHINE (PERCENT)   MM
AVERAGE SKY COVER           0.20
NUMBER OF DAYS FAIR           21
NUMBER OF DAYS PC              7
NUMBER OF DAYS CLOUDY          2

AVERAGE RH (PERCENT)     57

WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM              2     MIXED PRECIP               0
HEAVY RAIN                1     RAIN                       2
LIGHT RAIN               11     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.

$$

SEPTEMBER 2026 BROUGHT COOLER AND WETTER THAN NORMAL CONDITIONS TO
SOUTHEAST WASHINGTON INTO THE SOUTH IDAHO PANHANDLE.  THE FIRST HALF
OF THE MONTH WAS ACTIVE WITH SEVERAL ROUNDS OF PRECIPITATION. THE
12TH AND 13TH WAS ESPECIALLY WET WITH WIDESPREAD RAIN, WITH ISOLATED
THUNDERSTORMS AROUND LEWISTON ON THE 13TH.  RAIN AMOUNTS FOR MOST
LOCATIONS RANGED FROM 0.50-1.00 INCH, WITH HIGHER AMOUNTS ON THE
IDAHO PALOUSE WITH REPORTS UP TO 1.51 INCHES IN MOSCOW. ON THE 25TH
A STRONG COLD FRONT PASSAGE BRINGING BRIEF RAIN FOLLOWED BY WINDY
CONDITIONS. WIND GUSTS RANGED MAINLY FROM 35 TO 45 MPH.

ONE RECORD WAS SET DURING THE MONTH AT THE LEWISTON AIRPORT. ON THE
3RD A DAILY PRECIPITATION RECORD OF 0.68 INCHES WAS SET.