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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RENO NV
240 AM PDT FRI MAY 22 2015

.SYNOPSIS...

A COUPLE MORE DAYS OF SHOWERS AND THUNDERSTORMS ALONG WITH BELOW
NORMAL TEMPERATURES ARE EXPECTED AS AN AREA OF LOW PRESSURE
REMAINS ANCHORED OVER THE WEST. SHOWER AND THUNDERSTORM COVERAGE
WILL DECREASE THROUGH THE MEMORIAL DAY WEEKEND WITH TEMPERATURES
GRADUALLY WARMING TO NEAR NORMAL. LOWER END CHANCES FOR SHOWERS
WILL LINGER INTO NEXT WEEK, BUT THE TREND IS TOWARDS DRIER AND
WARMER CONDITIONS.

&&

.SHORT TERM...

TODAY WILL BRING A REPEAT OF SHOWER AND THUNDERSTORM ACTIVITY
ACROSS THE SIERRA AND NORTHWEST NEVADA AS ANOTHER PIECE OF ENERGY
ROTATES INTO THE LONGWAVE TROUGH OVER THE WEST. FORECAST MODELS
ARE SHOWING 500 TO 1200 J/KG OF CAPE FOR A MOST UNSTABLE PARCEL,
BUT IT IS DOUBTFUL THIS WILL BE REALIZED DUE TO THE ABUNDANT CLOUD
COVER IN PLACE. HOWEVER, THOSE AREAS WHICH HAVE PARTIAL CLEARING
WILL SEE CONVECTIVE ACTIVITY BEGIN BY LATE MORNING, WITH THE
POSSIBILITY FOR SOME STORMS TO BECOME STRONG. ELSEWHERE, SHOWERS
AND THUNDERSTORMS ARE LIKELY TO BEGIN BY NOON WITH THE OVERALL
MOVEMENT FROM THE NORTH/NORTHEAST. THE PRIMARY THREATS WILL BE
MODERATE TO HEAVY RAINFALL ALONG WITH SMALL HAIL. IF CELLS BEGIN
TO TRAIN, ESPECIALLY OVER TERRAIN WHICH HAS SEEN SIGNIFICANT
RAINFALL RECENTLY, OR OVER RECENT BURN SCARS, LOCALIZED, SHORT-
LIVED FLOODING MAY BE POSSIBLE.

WHILE GENERAL TROUGHINESS STAYS OVER THE WEST THROUGH THE HOLIDAY
WEEKEND, THE AFOREMENTIONED LOW BEGINS TO SHIFT OUT OF THE REGION
ON SATURDAY. THIS WILL LEAD TO A DECREASE IN SHOWER AND
THUNDERSTORM COVERAGE, WITH THE BEST CHANCES ACROSS THE CENTRAL
NEVADA BASIN AND RANGE ON SATURDAY. ANOTHER SHORTWAVE DROPS INTO
NORTHWEST NEVADA SUNDAY, BRINGING CHANCES FOR ADDITIONAL SHOWERS
AND THUNDERSTORMS, BUT COVERAGE IS EXPECTED TO BE LESS THAN THE
PAST FEW DAYS. A GRADUAL WARMING TREND WILL TAKE PLACE THROUGH THE
WEEKEND, BUT TEMPERATURES WILL STILL BE BELOW NORMAL. 

A FUN FACT - THE AVERAGE TEMPERATURE AT THE RENO AIRPORT (HIGH
AND LOW AVERAGED TOGETHER) HAS NOW BEEN BELOW NORMAL (ALBEIT NOT
MUCH BELOW) FOR 10 DAYS STRAIGHT. THE LAST TIME THE AVERAGE
TEMPERATURE HAS BEEN BELOW NORMAL FOR THAT MANY DAYS IN A ROW WAS
DECEMBER 2013! DJ

.LONG TERM...MONDAY THROUGH THURSDAY... 

MADE A FEW CHANGES TO THE LONG TERM WITH THE MODELS IN BETTER 
AGREEMENT THIS MORNING. THEY ARE TRENDING TOWARD MORE RIDGING THE 
MIDDLE AND END OF NEXT WEEK. THIS WOULD LIKELY RESULT IN SOME DRYING 
AND ALSO WARMER TEMPERATURES. 

LOW PRESSURE IS EXPECTED TO MOVE INTO WASHINGTON MONDAY AND TUESDAY 
WITH LIGHT WEST FLOW ALOFT UNDER THE TROUGH. WHILE THIS PATTERN IS 
NOT NORMALLY CONDUCIVE TO CONVECTION, LIGHT FLOW OVER THE WEEKEND 
WILL NOT SCOUR THE MOISTURE AND PERMIT A FEW SHOWERS AND 
THUNDERSTORMS EACH AFTERNOON WITH NEAR SEASONABLE TEMPERATURES IN 
THE 60S AND 70S. 

FOR WEDNESDAY AND THURSDAY, THE EC IS MORE PROGRESSIVE WITH THE LOW 
THAN THE GFS. WITH SOME RESIDUAL MOISTURE, ISOLATED SHOWERS AND 
THUNDERSTORMS REMAIN A POSSIBILITY BUT ARE LOOKING MORE REMOTE. AT 
THIS POINT, WITH THE MODELS AGREEING ON RISING HEIGHTS AND WARMER 
TEMPS ALOFT, BELIEVE THE CONVECTION WILL BE FOCUSED DURING THE DAY 
AND DRIED OUT OVERNIGHT. ALSO WARMED THE TEMPS A BIT WITH HIGHS NEAR 
80 IN WESTERN NV POSSIBLE TOWARD THE END OF NEXT WEEK. CONFIDENCE 
OVERALL REMAINS LOW THOUGH WEDNESDAY AND BEYOND WITH THE MODELS
STILL INCONSISTENT AND HIGH SPREAD IN THE ENSEMBLES. WALLMANN

&&

.AVIATION...

MVFR CONDS IN THE SIERRA THIS MORNING WITH OCNL -RA AND 
MTN OBSCN. MORE SHOWERS AND ISOLATED THUNDERSTORMS THIS AFTERNOON 
WITH THE PEAK PERIOD BETWEEN 19 AND 00Z. AREAS OF MVFR CONDS TO 
CONTINUE IN THE SIERRA INTO THE AFTERNOON AND EVENING WITH CIGS NEAR 
4-5000 FEET FOR WRN NV AT LEAST THRU 06Z. WINDS ARE EXPECTED TO 
REMAIN LIGHT OVERALL. MORE SHOWERS SATURDAY, BUT EXPECTED TO HAVE 
LESS COVERAGE AND IMPACTS COMPARED TO TODAY AND THE LAST 2 DAYS. 
WALLMANN

&&

.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&

$$

FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)

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