Flash Flood Guidance
Issued by NWS

Home | Current Version | Previous Version | Text Only | 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
000
AWUS01 KWNH 022224
FFGMPD
TNZ000-MOZ000-ARZ000-OKZ000-030358-

MESOSCALE PRECIPITATION DISCUSSION 0291...CORRECTED
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
623 PM EDT THU JUL 02 2015

CORRECTED FOR TYPOS

AREAS AFFECTED...NORTHEASTERN OK...NORTHERN AR...FAR SOUTHWESTERN
MO...EASTERN TN

CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE

VALID 022158Z - 030358Z

SUMMARY...BACKBUILDING/TRAINING CONVECTION ALONG A SLOW MOVING
FRONTAL BOUNDARY MAY PRODUCE LOCAL AMOUNTS OF 2-3 INCHES..WHICH
MAY CAUSE FLASH FLOODING

DISCUSSION...THE LATEST HI-RES GUIDANCE CONTINUES TO SHOW
CONVECTION DEVELOPING OVER THE NEXT SEVERAL HOURS FROM EASTERN TN
BACK ACROSS NORTHERN AR..ALONG AN EAST-WEST ORIENTED FRONTAL
BOUNDARY EXTENDING ACROSS THE REGION.  THE LATEST MESOANALYSIS
SHOWS MUCAPE VALUES OF 3000-4000 J/KG AND PWS OF 1.7-1.9 INCHES
ALONG THE BOUNDARY.  A SHORTWAVE TROUGH DIGGING SOUTHEASTWARD
THROUGH THE CENTRAL PLAINS-MID MS VALLEY IS EXPECTED TO PROVIDE
THE SYNOPTIC SCALE ASCENT NECESSARY FOR CONTINUED DEVELOPMENT
THROUGH THE EVENING.

THE LATEST RAP SHOWS A PERSISTENT WESTERLY LOW JET MAINTAINING PWS
OF 1.75-2 INCHES ALONG THE BOUNDARY THROUGH THE EVENING HOURS.
THE COMBINATION OF PERSISTENT MOIST LOW LEVEL INFLOW AND UPPER
LEVEL DIFFLUENCE IS EXPECTED TO SUPPORT BACKBUILDING CONVECTION
AND THE POTENTIAL FOR DOWNSTREAM TRAINING. OVER THE NEXT SEVERAL
HOURS...MOST OF THE HI-RES GUIDANCE AGREES THAT LOCALLY HEAVY
AMOUNTS ON THE ORDER OF 1-2 INCHES ARE POSSIBLE ACROSS PORTIONS OF
NORTHERN AR TO EASTERN TN.  MEANWHILE CONVECTION NOW DEVELOPING
OVER SOUTHEASTERN KS AND NORTHEASTERN OK IS EXPECTED TO FILL IN
ALONG THE WESTERN FLANK OF THE BOUNDARY EXTENDING ACROSS OK.  MUCH
OF THE HI-RES GUIDANCE SHOWS A PERIOD OF BACKBUILDING/TRAINING
HERE AS WELL...BEFORE THE DEVELOPING COLD POOLS ENCOURAGE
CONVECTION FURTHER TO THE SOUTH INTO SOUTHEASTERN OK.  HI-RES
CONSENSUS IS FOR SOME HEAVIER AMOUNTS ON THE ORDER OF 2-3 INCHES
ACROSS NORTHEASTERN OK.

THE LATEST ONE AND THREE HOUR FLASH FLOOD GUIDANCE VALUES SUGGEST
THE GREATER POTENTIAL FOR FLASH FLOODING CENTERS OVER NORTHERN AR
TO EASTERN TN..WHERE THE VALUES ARE RELATIVELY LOWER.
HOWEVER..EVEN FURTHER TO THE WEST WHERE VALUES ARE RELATIVELY
HIGHER..LOCAL RAINFALL RATES MAY APPROACH THE LATEST FLASH FLOOD
GUIDANCE VALUES.

PEREIRA

...PLEASE SEE WWW.WPC.NCEP.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...LZK...MEG...OHX...OUN...TSA...

ATTN...RFC...ABRFC...LMRFC...

LAT...LON   36899762 36409430 36229259 36199067 36388793
            35798800 35388876 35188994 35119182 35339369
            35549541 35659665 36289778 36669847


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