Quantitative Precipitation Forecast
Issued by NWS

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FOUS30 KWBC 100300
QPFERD

EXCESSIVE RAINFALL DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1059 PM EDT WED JUL 09 2014

...VALID 03Z THU JUL 10 2014 - 00Z FRI JUL 11 2014...
...REFERENCE AWIPS GRAPHIC UNDER...DAY 1 EXCESSIVE RAINFALL...



...CENTRAL NEBRASKA TO CENTRAL KANSAS...

DEVELOPING MCS ACROSS NEBRASKA LATE THIS EVENING IS BEING FUELED
BY AN INCREASING NOCTURNAL LLJ (25 KTS CURRENTLY PER THE LATEST
VWPS...EXPECTED TO PEAK BTWN 35-40 KTS OVERNIGHT) ALONG A
SECONDARY MAXIMA OF PW (1.5+ INCHES). COMPARATIVELY
SPEAKING...DEEP LAYER INSTABILITY IN THIS ENVIRONMENT IS NOT AS
ROBUST (MUCAPES BTWN 1000-2000 J/KG). FURTHERMORE...GIVEN THE
DEGREE OF WESTERLY FLOW ALOFT (DIRECTIONAL SHEAR) AND
NORTHWESTERLY 0-6KM BULK SHEAR OF 40-50 KTS...THE ACTIVITY THUS
FAR HAS CLEARLY EXHIBITED ENHANCED FORWARD (DOWNWIND) PROPAGATION.
NEVERTHELESS...THE CONCERN OVERNIGHT WILL BE WITH ADDITIONAL CELLS
DEVELOPING UPSTREAM IN THE COOL SECTOR NORTH OF A SURFACE
STATIONARY BOUNDARY WHICH IS BEING ENHANCED BY THE OUTFLOWS...AS
THE STRENGTHENING SRLY LLVL INFLOW OPPOSING THE NORTHERLY CORFIDI
VECTORS. SOME OF THE LATEST MESOSCALE GUIDANCE...INCLUDING THE
PARALLEL VERSION OF THE 4KM NAM CONEST... SUGGEST ISOLATED AMOUNTS
OVER 4 INCHES WILL BE POSSIBLE WITHIN A FEW HOURS...WHICH COULD
LEAD TO LOCALIZED RUNOFF ISSUES AND FLASH FLOODING. FOR FURTHER
DETAILS...PLEASE REFER TO THE LATEST MESOSCALE PRECIPITATION
DISCUSSION (FFGMPD #183) AT
WWW.WPC.NCEP.NOAA.GOV/METWATCH/METWATCH_MPD.PHP.


...SOUTHWESTERN U.S. INTO THE GREAT BASIN...

THE RECENT MONSOONAL PATTERN IS SHOWING NO SIGNS OF SIGNIFICANT
CHANGE THIS PERIOD.  WATER VAPOR IMAGERY CONTINUES TO SHOW A
MOISTURE PLUME STRETCHING FROM NORTHWEST MEXICO INTO THE GREAT
BASIN AND SOUTHWEST ON THE SOUTH AND WEST SIDES OF THE GREAT BASIN
UPPER HIGH. PWS IN THIS PLUME WILL CONTINUE OVER 150 PCT OF NORMAL
IN SOME SPOTS.  WEAK IMPULSES REMAIN EMBEDDED WITHIN AND ON THE
PERIPHERY OF THE MEAN UPPER HIGH OVER THE GREAT BASIN AND WILL
SUPPORT ADDITIONAL SCATTERED CONVECTION IN THIS HIGH PW AXIS.
CONFIDENCE REMAINS LOW WITH PLACEMENT OF CONVECTIVE AREAS.
HOWEVER---THE RECENT PATTERN OF ISOLATED ORGANIZED CONVECTIVE
AREAS SHOULD CONTINUE THIS PERIOD WITH ISOLATED RUNOFF ISSUES
POSSIBLE WHERE CONVECTION DOES ORGANIZE.  FLASH FLOOD GUIDANCE IS
HIGH AT 3-4 INCHES IN 6 HOURS AND GLOBAL MODEL HIGH RES WRF
ARW/NMM QPF IS WELL BELOW THESE NUMBERS.

PETERSEN/HURLEY
$$




USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.