Skip Navigation Links weather.gov 
NOAA logo - Click to go to the NOAA homepage National Weather Service   NWS logo - Click to go to the NWS homepage
The Weather Prediction Center

 
 

 

Follow the Weather Prediction Center on Facebook Follow the Weather Prediction Center on Twitter
NCEP Quarterly Newsletter
WPC Home
Analyses and Forecasts
   National High & Low
   WPC Discussions
   Surface Analysis
   Days ½-2½ CONUS
   Days 3-7 CONUS
   Days 4-8 Alaska
   QPF
   PQPF
   Flood Outlook
   Winter Weather
   Storm Summaries
   Heat Index
   Air Quality
   Tropical Products
   Daily Weather Map
   GIS Products
Current Watches/
Warnings

Satellite and Radar Imagery
   Satellite Images
   National Radar
Product Archive
WPC Verification
   QPF
   Medium Range
   Model Diagnostics
   Event Reviews
International Desks
Development and Training
   Development
WPC Overview
   About the WPC
   Staff
   WPC History
   Accomplishments
   Other Sites
   FAQs
Meteorological Calculators
Contact Us
   About Our Site
 
USA.gov is the U.S. Government's official web portal to all federal, state, and local government web resources and services.
 
Excessive Rainfall Discussion
 
(Caution: Version displayed is not the latest version. - Issued 0100Z Jul 26, 2014)
 
Version Selection
Versions back from latest:  0   1   2   3   4   5   6   7   8   9   10   
 
Abbreviations and acronyms used in this product
 
Geographic Boundaries -  Map 1: Color  Black/White       Map 2: Color  Black/White


EXCESSIVE RAINFALL DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
900 PM EDT FRI JUL 25 2014

...VALID 00Z SAT JUL 26 2014 - 00Z SUN JUL 27 2014...
...REFERENCE AWIPS GRAPHIC UNDER...DAY 1 EXCESSIVE RAINFALL...


SLIGHT RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
45 ESE HXD 15 ESE SVN 15 SE TBR 10 NW JYL 25 SSE AGS 35 ESE AGS
15 WNW NBC 35 S CHS 60 SE CHS 45 ESE HXD.


...SOUTH CAROLINA...

03Z UPDATE...
SOME LINGERING HEAVY TO EXCESSIVE RAIN POTNL THRU THE EARLY
OVERNIGHT OVER EXTREME SRN SC INTO BORDERING GA AS LATE AFTN TSTM
ACTIVITY OVER GA/SRN SC CONTINUES TO TRACK GENL EWD AND ACTS ON
REMAINING DAYTIME INSTABILITIES/CAPE SOUTH OF COLD FRONT.   LATEST
RADAR INDICATED SOME NEARLY STATIONARY E/W BANDS ACRS THE SRN
SC/GA BORDER THAT COULD PRODUCE SOME QUICK 1 TO 2 INCH RAINFALL
AMOUNTS..THOUGH OVERALL TREND SHOULD BE TOWARD LESS ORGANIZED
ACTIVITY AS THE OVERNIGHT WEARS ON AND SLIGHTLY DRIER AIR MOVES IN
FROM THE WEST.


...COLORADO...

WHILE A GRADUAL DIMINISHING OF DIURNALLY DRIVEN CNVTN SHOULD
CONTINUE OVERNIGHT WITH LESSENING OF ANY FF THREAT...WEAK IMPULSES
RIDING OVER THE SRN SRN ROCKIES RIDGE THROUGH CO WILL ACT ON A
PLUME OF MOISTURE WITHIN THE RIDGE RESULTING IN ADDITIONAL
CONVECTION MOST LIKELY DURING THE AFTN/EVEN ON SAT.  WEAKENING
FLOW ALOFT..ESPECIALLY OVER SRN PORTIONS OF CO COULD LEAD TO SOME
SLOWER MOVING STORMS CAPABLE OF PRODUCING SOME INSTANTANEOUS RATES
NEARING AN INCH PER HOUR AND AT LEAST AN ISOLATED THREAT OF RUNOFF
ISSUES...PARTICULARLY OVER SUSCEPTIBLE TERRAIN/BASINS.


...FAR SOUTHWEST U.S...

FORECASTS FROM THE RAP AND THE GLOBAL SCALE MODELS INDICATE A
PLUME OF ENHANCED MID LEVEL MOISTURE WILL ADVECT THROUGH THE LOW
DESERT IN WESTERN AZ/SOUTHERN CA TODAY...REACHING THE MOUNTAINOUS
TERRAIN BETWEEN FLAGSTAFF...LAS VEGAS...AND NORTHWEST OF NEEDLES
BY AFTERNOON. THE 12Z TUSCON SOUNDING MAY BE MOST REPRESENTATIVE
OF THIS ENVIRONMENT. INSTABILITY SHOULD BE SUFFICIENT TO SUPPORT
DIURNAL THUNDERSTORMS ACROSS NORTHWEST AZ AND ADJACENT
STATES...AND ENHANCED 850-700 MB SOUTHERLY FLOW OF 15-25 KNOTS
AROUND THE PERIPHERY OF THE MID LEVEL RIDGE MAY LEND SOME
ORGANIZATION TO THE CONVECTION ON A LOCAL SCALE...ALLOWING FOR
SOME REDEVELOPMENT ALONG OUTFLOWS. TEMP/DEWPOINT SPREADS REMAIN
FARLY LARGE...HOWEVER...AND THE QPF SIGNAL FROM THE HIGH
RESOLUTION GUIDANCE IS SPOTTY AND SMALL SCALE...SUGGESTING PERHAPS
A VERY ISOLATED FLASH FLOOD RISK IN THE MOST SUSCEPTIBLE TERRAIN
AND/OR WATER CHANNELS. FARTHER SOUTH...THE MODELS HAVE BECOME MORE
AGGRESSIVE IN THE COVERAGE AND INTENSITY OF PRECIPITATION
EMANATING FROM THE MOUNTAINS AROUND TUSCON...ALTHOUGH CELL MOTIONS
AWAY FROM THE UNSTABLE INFLOW COULD LIMIT THE POTENTIAL FOR
TRAINING.

BURKE/SULLIVAN