Hydrometeorological Discussion
Issued by NWS California-Nevada RFC

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AGUS76 KRSA 141751
HMDRSA

- KHMD 141707
WRKHMD

HYDROMETEOROLOGICAL DISCUSSION
NATIONAL WEATHER SERVICE / CALIFORNIA NEVADA RFC / SACRAMENTO CA
930 AM PST SUN FEB 14 2016

...LIGHT PRECIP IN THE NORTH THROUGH EARLY MON...
...WETTER WEATHER RETURNS WED-FRI...

.24 HOUR PRECIPITATION TOTALS (ENDING FEB 14 AT 400 AM PST)...

WARM ADVECTION BROUGHT LIGHT PRECIP TO THE FAR NORTH COAST AND UPPER
KLAMATH BASIN BEGINNING SAT EVENING.  AMOUNTS WERE NEAR 0.1" OR LESS.


.METEOROLOGICAL CONDITIONS (SUN AM - SAT AM)...

LIGHT PRECIP IS FALLING ACROSS PORTIONS OF FAR NRN CA/NV AND SRN
OREGON.  PRECIP OVER CA/OR CAN BE ATTRIBUTED TO ISENTROPIC LIFT IN A
MOIST AIR MASS, WHILE PRECIP OVER NRN NV IS DOMINATED BY DIVERGENCE
ALOFT WITH AN UPPER JET NEARBY.  EXPECT PRECIP TO GRADUALLY WIND
DOWN THROUGH EARLY MON.  ALTHOUGH UPPER DIVERGENCE DECREASES BY THIS
AFTERNOON OVER NE NV, WEAK DISTURBANCES COULD KEEP PRECIP GOING INTO
EARLY MON.  EXPECT FREEZING LEVELS AROUND 8000-10000 FT.

RIDGING SHOULD PROVIDE A PERIOD OF DRY WEATHER MON THROUGH TUE
NIGHT.   A WETTER SYSTEM IS EXPECTED FOR WED-THU AND SHOULD AFFECT
ALMOST ALL OF THE REGION PERHAPS WITH THE EXCEPTION OF FAR SE CA AND
FAR SRN NV.  MODEL AGREEMENT WAS DECENT BETWEEN THE 00 UTC RUNS OF
THE GFS AND ECMWF, AND A BLEND OF THE TWO WAS USED AS A BASIS FOR
THE FORECAST FOR THIS STORM.  THE NEW 12 UTC RUN IS IN REASONABLE
AGREEMENT WITH OUR FORECAST FOR THE MOST PART.

EXPECT LIGHT PRECIP TO BEGIN IN NW CA WED MORNING AS A WEAK
SHORTWAVE MOVES INTO THE AREA AHEAD OF THE MAIN SYSTEM AND AN UPPER
JET BEGINS TO CAUSE DIVERGENCE ALOFT.  EXPECT PRECIP TO RAMP UP AND
SPREAD INLAND AND SWD TO PORTIONS OF SRN CA WED AFTERNOON AND
EVENING AS THE MAIN SHORTWAVE AND COLD FRONT APPROACH THE COAST AND
AN UPPER JET CUTS ACROSS CNTRL CA WITH SPEEDS OF 130 KTS AND ABOVE.
LIGHT TO MODERATE PRECIP ACROSS NRN/CNTRL CA SHOULD BE DOMINATED BY
DYNAMICS ALOFT WITH MOISTURE LACKING, AND PRECIP MAINLY SOUTH OF PT
CONCEPTION SHOULD BE LIGHT EXCEPT HEAVIER IN COASTAL TERRAIN AND
MAINLY DOMINATED BY A WEAK ONSHORE FLOW AND WEAK DIVERGENCE ALOFT
INTERACTING WITH A NARROW MOISTURE PLUME WITH PW VALUES AROUND 1".
HEAVIEST AMOUNTS OVERALL ARE EXPECTED ACROSS MUCH OF NRN/CNTRL CA
WITH THE EXCEPTION OF THE SACRAMENTO VALLEY, AND PORTIONS OF SRN
OREGON.  PRECIP IS EXPECTED TO WIND DOWN FOR THE MOST PART THU
NIGHT.  EXPECT FREEZING LEVELS TO START OFF AROUND 8000-10000 FT AND
LOWER TO 4500-7000 FT (EXCEPT 8000 FT AND ABOVE FOR SRN CA) BY THU
MORNING.

ANOTHER SYSTEM SHOULD BRING ADDITIONAL PRECIPITATION TO MAINLY NRN
CA/SRN OREGON FRI.  EXPECT FREEZING LEVELS 4000-6000 FT.


.HYDROLOGICAL CONDITIONS...

MOST RIVERS AND STREAMS IN THE CNRFC FORECAST AREA ARE RECEDING
SLOWLY...OR FLUCTUATING NEAR PRESENT LEVELS.  PRECIPITATION FORECAST
TO BEGIN ON WEDNESDAY IS EXPECTED TO PRODUCE MINOR RISES IN STAGE BY
THURSDAY MORNING.

ALL RIVER AND STREAMS ARE CURRENTLY BELOW...AND ARE FORECAST TO
REMAIN BELOW MONITOR LEVELS THROUGH FRIDAY MORNING.


MORE INFORMATION ON THE CNRFC WEBSITE AT HTTP://WWW.CNRFC.NOAA.GOV

KL/SS

$$



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