MESOSCALE PRECIPITATION DISCUSSION 0012
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
410 AM EST TUE JAN 19 2016
 
AREAS AFFECTED...NORTHERN CA COAST... 
 
CONCERNING...HEAVY RAINFALL 
 
VALID 190910Z - 191810Z
 
SUMMARY...RECENT WATER VAPOR IMAGERY AND AMSU PASS INFORMATION
DEPICTED A WELL DEFINED SHORTWAVE CURRENTLY NEARING 40N/130W. THIS
PROGRESSIVE SYSTEM WILL SPREAD RAINFALL TO THE NORTHERN CA COAST
WITH HOURLY RATES APPROACHING 0.50 INCHES. GIVEN RECENT HEAVY
RAINFALL ACROSS NORTHERN SECTIONS OF THE MPD...EXPECT THE
POSSIBILITY OF LOCALIZED HYDROLOGIC ISSUES IN SOME OF THE MORE
CONCENTRATED RADAR ECHOES.

DISCUSSION...A PROGRESSIVE SHORTWAVE WILL CONTINUE TO MARCH
EASTWARD REACHING THE NORTHERN CA COAST BY THIS MORNING. EVALUTION
OF RECENT AMSU DATA INDICATES HOURLY RAINFALL RATES HAVE COME DOWN
QUITE A BIT WITH VALUES MAXIMIZING AROUND 0.50 INCHES.
HOWEVER...OTHER ASPECTS OF THE SYSTEM STILL REMAIN INTACT WITH
CLOUD TOP TEMPERATURES NOT CHANGING MUCH AND PWATS UP TO 1.75
INCHES WITHIN THE CORE OF THE MOISTURE CHANNEL. THESE ENHANCED
MOISTURE FLUXES WILL CONTINUE ADVECTING EASTWARD WITH RATHER
IMPRESSIVE 850-700 MB ANOMALIES NEARING THE 3 TO 4 SIGMA RANGE BY
15Z. THIS COUPLED WITH A HINT OF WEAK INSTABILITY PER RECENT RAP
MODEL RUNS SUGGEST THE THREAT FOR ENHANCED RAINFALL
RATES...PARTICULARLY IN REGIONS OF COMPLEX TERRAIN. THE OVERALL
IMPACTS SHOULD BE OF A SHORTER DURATION GIVEN THE QUICK MOVING
NATURE OF THE SHORTWAVE. RECENT CAMS INDICATE 1 TO 1.50 INCHES OF
RAINFALL IN 6 HOURS IS POSSIBLE WITH LOCAL MAXIMA PERHAPS
APPROACHING 2 INCHES.

AFTER COORDINATION WITH WFOS EKA/MTR...LOCAL RIVERS ACROSS THE
AFFECTED AREAS COULD SEE HYDROLOGIC RESPONSES WITH THE EXPECTED
MODERATE/HEAVY RAINFALL. THIS IS PARTICULARLY THE CASE ACROSS THE
NORTHERN SECTOR OF THE MPD WHERE STAGE IV GAUGE DATA SHOWED 3 TO 5
INCHES OF PRECIPITATION FELL THROUGH MONDAY MORNING. HOWEVER...THE
SHORT DURATION OF THIS EVENT SHOULD MITIGATE ANY MORE SIGNIFICANT
ISSUES.


RUBIN-OSTER

ATTN...WFO...EKA...MTR...STO...

ATTN...RFC...CNRFC...

LAT...LON   40552336 39242221 38522167 37662138 36682141 
            36522223 37772313 38742385 40372459