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000
CXUS56 KMFR 011236 AAA
CLMMFR

CLIMATE REPORT
NATIONAL WEATHER SERVICE MEDFORD, OR
536 AM PDT FRI SEP 01 2023

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

...THE MEDFORD OR CLIMATE SUMMARY FOR THE MONTH OF AUGUST 2023...

CLIMATE NORMAL PERIOD 1991 TO 2020
CLIMATE RECORD PERIOD 1911 TO 2023

WEATHER         OBSERVED          NORMAL  DEPART   LAST YEAR`S
                VALUE   DATE(S)   VALUE   FROM     VALUE DATE(S)
                                          NORMAL
................................................................
TEMPERATURE (F)
RECORD
 HIGH            114   08/08/1981
 LOW              39   08/27/1962
HIGHEST          111   08/14                         103  08/03
LOWEST            53   08/30                          56  08/28
AVG. MAXIMUM    93.6               91.1     2.5     95.7
AVG. MINIMUM    63.2               57.9     5.3     62.4
MEAN            78.4               74.5     3.9     79.1
DAYS MAX >= 90    24               20.1     3.9       28
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        2.83   1976
TOTALS          0.07               0.33   -0.26        T
DAILY AVG.      0.00               0.01   -0.01        T
DAYS >= .01        1                1.6    -0.6        0
DAYS >= .10        0                0.8    -0.8        0
DAYS >= .50        0                0.2    -0.2        0
DAYS >= 1.00       0                0.0     0.0        0
GREATEST
 24 HR. TOTAL   0.07   08/31 TO 08/31

SNOWFALL (INCHES)
RECORDS
 TOTAL           0.0   2010
TOTALS           0.0                0.0     0.0      0.0
SINCE 7/1        0.0                0.0     0.0       MM

DEGREE DAYS
HEATING TOTAL      0                  3      -3        0
 SINCE 7/1         0                  4      -4       MM
COOLING TOTAL    421                298     123      442
 SINCE 1/1      1155                767     388       MM

FREEZE DATES
RECORD
 EARLIEST     09/13/1921
 LATEST       06/12/1952
EARLIEST                        MM
LATEST                          04/13
................................................................

WIND (MPH)
AVERAGE WIND SPEED              4.2
HIGHEST WIND SPEED/DIRECTION    24/210    DATE  08/19
                                24/160          08/20
HIGHEST GUST SPEED/DIRECTION    38/200    DATE  08/19

SKY COVER
POSSIBLE SUNSHINE (PERCENT)   MM
AVERAGE SKY COVER           0.17
NUMBER OF DAYS FAIR           25
NUMBER OF DAYS PC              2
NUMBER OF DAYS CLOUDY          3

AVERAGE RH (PERCENT)     43

WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM              2     MIXED PRECIP               0
HEAVY RAIN                0     RAIN                       0
LIGHT RAIN                4     FREEZING RAIN              0
LT FREEZING RAIN          0     HAIL                       0
HEAVY SNOW                0     SNOW                       0
LIGHT SNOW                0     SLEET                      0
FOG                       1     FOG W/VIS <= 1/4 MILE      0
HAZE                     28

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

&&

AUGUST 2023 SHOWED A WIDE RANGE IN THE WEATHER, BUT WAS OVERALL
TYPICAL FOR THE AREA. AUGUST STARTED OFF TYPICALLY WITH DRY WEATHER
AND TEMPERATURES THAT WERE NOT TOO HOT. AFTER THE FIRST DAY OF THE
MONTH WHICH SAW A HIGH OF 98 DEGREES, AFTERNOON HIGHS ONLY REACHED
INTO THE LOW TO MID 90S THROUGH THE FIRST 10 DAYS. CONDITIONS
STARTED TO HEAT UP AND DRY OUT, AND BY MID MONTH, WE EXPERIENCED A 4-
DAY HEATWAVE THAT BROUGHT EXTREME TEMPERATURES TO MOST INLAND AREAS
WEST OF THE CASCADES. TEMPERATURES SOARED INTO THE TRIPLE DIGITS
ONCE AGAIN, AND AT THE PEAK OF THE HEATWAVE ON THE 14TH, MEDFORD SAW
A HIGH OF 111 DEGREES WHICH BROKE THE DAILY RECORD OF 108 SET BACK
IN 1933.

AS IS TYPICAL WITH THESE HEATWAVES, THEY END WITH A PATTERN CHANGE
THAT BRINGS THUNDERSTORMS TO THE AREA. THIS THUNDERSTORM PATTERN WAS
PART OF A SLOW MOVING LOW PRESSURE SYSTEM THAT TRAVELED NORTHWARD
THROUGH CALIFORNIA BEFORE PASSING THROUGH OREGON AND NORTHEAST INTO
IDAHO. THIS BROUGHT MULTIPLE DAYS OF THUNDERSTORMS TO THE AREA (FROM
THE 15TH THROUGH THE 21ST AND THEN AGAIN ON THE 24TH). IN ALL, LAKE
COUNTY WAS OUR WINNER WITH 796 LIGHTNING STRIKES FOLLOWED BY
SISKIYOU COUNTY WITH 642 LIGHTNING STRIKES IN THAT STRETCH.
MEANWHILE, JACKSON COUNTY WAS THIRD WITH 342 LIGHTNING STRIKES.
HOWEVER, EVERY COUNTY IN OUR AREA RECORDED AT LEAST 20 STRIKES (EVEN
COOS AND CURRY COUNTIES).

THE MAJOR THUNDERSTORM DAYS THAT WOULD IMPACT THE WEATHER IN THE
ROGUE VALLEY WERE THE 15TH WHERE THUNDERSTORMS PUSHED THROUGH
WESTERN SISKIYOU COUNTY; THE 19TH WHERE JACKSON COUNTY HAD 279 OF
THEIR 342 STRIKES; AND THE 21ST WHERE DOUGLAS COUNTY SAW 85
LIGHTNING STRIKES. THESE THREE DAYS ARE THE MOST LIKELY CULPRITS FOR
THE STARTS OF ONGOING WILDFIRES IN THE AREA.

ADDITIONALLY, DURING THIS TIME, THE LOW PRESSURE SYSTEM TAPPED INTO
DEEP TROPICAL MOISTURE FROM THE REMNANTS OF HURRICANE HILARY. THIS
PARTICULAR INTERACTION HAPPENED ON THE 21ST AND BROUGHT SIGNIFICANT
RAINFALL TO PORTIONS OF NORTHERN CALIFORNIA AND AREAS EAST OF THE
CASCADES IN SOUTHERN OREGON. KLAMATH FALLS SAW OVER HALF AN INCH OF
RAINFALL IN A 24 HOUR PERIOD FROM THIS. IN ADDITION, MT. SHASTA CITY
SAW 0.62 INCHES OF RAIN AND THIS BAND OF HEAVY RAIN CAUSED A DEBRIS
FLOW ALONG EVERITT MEMORIAL HIGHWAY, STRANDING  PEOPLE ON MT.
SHASTA. JUXTAPOSED WITH THIS BAND OF HEAVY RAIN WAS AN AREA OF THICK
WILDFIRE SMOKE FROM SEVERAL WILDFIRE COMPLEXES IN NORTHERN
CALIFORNIA AND SOUTHERN OREGON. ALONG THE BORDER OF THESE TWO
WEATHER PATTERNS, A THUNDERSTORM DEVELOPED OVER THE MCKINNEY BURN
SCAR BRINGING OVER AN INCH OF RAIN IN AN HOUR CAUSING DEBRIS FLOWS
AT THE BURN SCAR.

ON THE 24TH, ANOTHER SET OF THUNDERSTORMS PUSHED NORTHWARD WEST OF
INTERSTATE 5 AND ALSO FOR PORTIONS OF LAKE COUNTY. WHAT IS NOTABLE
ABOUT THESE THUNDERSTORMS IS THAT THEY MOVED THROUGH AREAS OF THICK
SMOKE WHICH LIKELY CAUSED A CHARGE REVERSAL IN THE THUNDERSTORMS.
DURING A THUNDERSTORM, ICE CRYSTALS CREATE STATIC ELECTRICITY,
CALLED CHARGE SEPARATION, AND NEGATIVE IONS GATHER AT THE BOTTOM OF
THE CLOUD AND POSITIVE IONS GATHER AT THE TOP OF THE CLOUD. WHEN
ENOUGH CHARGE BUILDS UP, IT IS DISPERSED IN A LIGHTNING STRIKE,
CODED AS POSITIVE OR NEGATIVE BASED ON THE IONS THAT ARE TRAVELLING.
HOWEVER, WHEN THUNDERSTORMS OCCUR OVER DENSE SMOKE, THE POSITIVE
CHARGES SHIFT AND BUILD AT THE BOTTOM OF CLOUDS AND NEGATIVE CHARGES
BUILD OVER THE TOP OF THE CLOUD, WHICH IS DENOTED AS A CHARGE
REVERSAL. FOR INSTANCE, JOSEPHINE COUNTY EXPERIENCED UNHEALTHY TO
HAZARDOUS AIR QUALITY ON THE 24TH AND SAW 48 LIGHTNING STRIKES THAT
DAY. ALL BUT 7 OF THE LIGHTNING STRIKES WERE POSITIVE; THUS
SUGGESTING A CHARGE REVERSAL HAD TAKEN PLACE.

MEANWHILE, THE ROGUE VALLEY BEGAN SUFFERING PERIODS OF DEGRADED AIR
QUALITY--REACHING HAZARDOUS LEVELS AT TIMES. THIS SMOKE WAS LARGELY
CAUSED BY THE SMITH RIVER COMPLEX, THE HAPPY CAMP COMPLEX, AND THE
TYEE FIRE; AND HAS CONTINUED THROUGH THE END OF THE MONTH. ANOTHER
HEATWAVE TRIED TO BUILD IN, BUT THE SMOKE LIKELY KEPT TEMPERATURES
FROM REACHING THEIR POTENTIAL--ONLY REACHING INTO THE 90S FROM THE
24TH THROUGH THE 26TH. THEN THE FIRST IN A SERIES OF FRONTS BEGAN
MOVING THROUGH, BRINGING GUSTY WEST WINDS TO THE AREA, WHICH BROUGHT
PERIODS OF IMPROVED AIR QUALITY FROM SMOKE AS WELL AS LOWER
TEMPERATURES. IN FACT, ON THE 31ST, MEDFORD SAW ITS FIRST MEASURABLE
RAINFALL SINCE JUNE 19TH WITH 0.07 INCHES.

$$