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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RENO NV
253 AM PDT SUN JUL 5 2015

.SYNOPSIS...
LOW PRESSURE NEAR THE CALIFORNIA COAST WILL KEEP THE THREAT FOR
SHOWERS AND THUNDERSTORMS THROUGH MUCH OF THE UPCOMING WEEK.
THUNDERSTORM COVERAGE WILL BE MORE ISOLATED TODAY, FOLLOWED BY 
AN INCREASED CHANCE FOR STRONGER STORMS WITH LOCALLY HEAVY
RAINFALL POSSIBLE MONDAY THROUGH THURSDAY.

&&

.SHORT TERM...

AREA OF MAINLY LIGHT RAIN CONTINUES OVER NORTHEAST CA-NORTHWEST NV
EARLY THIS MORNING, WITH SHORT RANGE GUIDANCE SLOWLY LIFTING THIS
RAIN TO THE NORTH DURING THE MORNING HOURS. ELSEWHERE, THE DAY
WILL BEGIN WITH LESS CLOUD COVER UNTIL DAYTIME HEATING LEADS TO
CUMULUS BUILDUPS WITH SHOWERS AND THUNDERSTORMS POSSIBLE THIS
AFTERNOON. SIGNIFICANT FORCING IS NOT EXPECTED TODAY, SO MOST
CELLS WILL LIKELY BE PULSE TYPE WITH BRIEF HEAVY RAINFALL, LOCALLY
GUSTY OUTFLOW WINDS AND POSSIBLE SMALL HAIL.

FOR MONDAY AND TUESDAY, THE UPPER LOW OFF THE CA COAST WILL PULL
MORE MOISTURE AND INSTABILITY INTO THE SIERRA AND WESTERN NV WITH
DIFFLUENT SOUTH TO SOUTHEAST FLOW ALOFT. MODEL GUIDANCE HAS BEEN
RELATIVELY CONSISTENT WITH KEEPING UPPER LEVEL DIVERGENCE ACROSS
EASTERN CA-WESTERN NV, WHICH WOULD LEAD TO STRONGER UPDRAFTS AND
MORE ORGANIZED CONVECTION EACH AFTERNOON AND EVENING. WE COULD BE
BACK INTO A THREAT FOR FLOODING WITH POTENTIAL FOR CELLS
REDEVELOPING OVER SAME AREAS, ALONG WITH AN INCREASED HAIL AND
WIND THREAT. MODEL SOUNDINGS APPEAR TO INDICATE ENOUGH CLEARING
EARLY IN THE DAY TO ALLOW FOR BETTER DEVELOPMENT OF AFTERNOON
STORMS. 

DAYTIME TEMPERATURES FOR THE NEXT FEW DAYS WILL BE NEAR SEASONAL
NORMALS OF LOWER 90S FOR LOWER ELEVATIONS AND 80-85 DEGREES FOR
SIERRA VALLEYS. MJD

.LONG TERM...WEDNESDAY THROUGH SATURDAY... 

OPERATIONAL MODELS AND MOST GEFS ENSEMBLE MEMBERS CONTINUE THE TREND 
FROM PREVIOUS MODEL RUNS OF SLOWLY LIFTING A CLOSED UPPER LOW INTO 
CALIFORNIA BY MID WEEK THEN OPENING THE LOW AS AN UPPER WAVE BY LATE 
FRIDAY. THIS WAVE THEN LIFTS NORTH OF THE AREA ON SATURDAY WITH AN 
INCREASE IN SOUTHWEST FLOW ALOFT.

MINOR CHANGES WERE MADE TO THE FORECAST...MAINLY TO START INCREASING 
POPS OVER THE FAR NORTHERN CWA WEDNESDAY THROUGH FRIDAY. THE RUN TO 
RUN CONSISTENCY WITH THE OVERALL PATTERN IS PRODUCING A HIGHER 
CONFIDENCE IN THE PRESENCE OF SHOWERS OVER THE FAR NORTHERN CWA AS A 
DEFORMATION ZONE COULD POSSIBLY DEVELOP SOMEWHERE TO THE NORTH AND 
EAST OF THE LOW. PICKING AN EXACT AREA IS DIFFICULT SO WE WILL BE 
FAIRLY BROAD BRUSHED. THE PRESENCE OF INCREASED CLOUDS EACH DAY AND 
A POSSIBLE SHIELD OF PCPN COULD LEAD TO LOWER HIGH TEMPERATURES AS 
WELL. THUS WE WILL START TO DROP THE HIGHS A BIT FOR WEDNESDAY 
THROUGH FRIDAY...BUT WILL STILL BE ABOVE MOST GUIDANCE.

SATURDAY SHOULD BE THE DRIEST DAY OVERALL AS THE WAVE STARTS TO PULL 
AWAY. WILL LEAVE SOME RESIDUAL POPS OVER THE FAR NORTH...BUT 
INCREASING SOUTHWEST FLOW ALOFT IS LIKELY TO LIMIT CONVECTIVE 
POTENTIAL SOUTH OF INTERSTATE 80 THAT DAY. HIGHS SHOULD ALSO BEGIN 
TO REBOUND TO NEAR OR SLIGHTLY ABOVE AVERAGE AS WELL. 20

&&

.AVIATION... 

THUNDERSTORMS ARE EXPECTED OVER WRN NV AND ERN CA EACH DAY THROUGH 
NEXT FRIDAY. COVERAGE WILL VARY EACH DAY AND THE LOCATION OF THE 
MOST ACTIVITY IS LIKELY TO VARY. ALL DAYS HAVE THE POSSIBILITY OF 
GUSTY SURFACE WINDS...SMALL HAIL...TURBULENCE NEAR STORMS AND
REDUCED VISIBILITY DUE TO THICK CLOUDS AND HEAVY RAIN.

WHILE VFR CONDITIONS ARE EXPECTED OUTSIDE OF STORMS EACH DAY...IN 
AND NEAR THE STORMS VSBY COULD BE QUITE LOW. ALSO AN ISSUE COULD BE 
OBSCURED MOUNTAIN TOPS DUE TO RAIN AND CLOUDS. AVIATION INTERESTS 
ARE ADVISED TO USE EXTREME CAUTION IN AND NEAR THUNDERSTORMS. 

LATER IN THE WEEK IT IS POSSIBLE THAT A MORE ORGANIZED AREA OF 
PRECIPITATION WITH SLIGHTLY LOWER CEILINGS IS POSSIBLE...ESPECIALLY 
NORTH OF INTERSTATE 80. IT IS TOO FAR OUT AT THIS POINT TO PINPOINT 
THE LOCATION OF LOWER CEILINGS FOR THIS PERIOD...WEDNESDAY AND 
THURSDAY...SO KEEP CHECKING BACK TO SEE HOW THE PATTERN DEVELOPS. 20

&&


.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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