MESOSCALE PRECIPITATION DISCUSSION 0122
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
612 PM EDT SUN MAY 24 2015
 
AREAS AFFECTED...EASTERN CO...FAR WESTERN KS...SOUTHWEST
NE...SOUTHEAST WY 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 242210Z - 250300Z
 
SUMMARY...SOME ADDITIONAL INCREASE IN SHOWER AND THUNDERSTORM
ACTIVITY IS EXPECTED THIS EVENING. LOCALLY INTENSE RAINFALL RATES
WILL BE POSSIBLE WHICH MAY RESULT IN SOME FLASH FLOODING GIVEN THE
WET ANTECEDENT CONDITIONS.

DISCUSSION...SATELLITE SHOWS TWO WELL-DEFINED VORT CENTERS
ROTATING AROUND EACH OTHER OVER...WITH ONE OVER SOUTHERN WY AND
ANOTHER EJECTING EAST ACROSS SOUTHERN CO. THE VORT OVER SOUTHERN
CO IS EJECTING OUT INTO THE HIGH PLAINS WHERE SUFFICIENT DIURNAL
HEATING THIS AFTERNOON HAS RESULTED IN A NOSE OF SBCAPE VALUES
APPROACHING 1500 J/KG FROM FAR SOUTHEAST CO NORTH UP ALONG THE
CO/KS BORDER. THE RESULT HAS BEEN AN EXPANSION THE LAST COUPLE OF
HOURS OF RELATIVELY COLD-TOPPED CONVECTION ACROSS EASTERN CO IN A
N/S FASHION.

OVER THE NEXT SEVERAL HOURS...THE CONVECTION SHOULD TEND TO BECOME
A BIT BETTER ORGANIZED AND EXPAND IN COVERAGE AS INSTABILITY
STRENGTHENS FURTHER AHEAD OF THE SHORTWAVE IMPULSE...AND SOUTH TO
SOUTHEAST LOW LEVEL WINDS ALLOW SURFACE MOISTURE TO INCREASE A
BIT. THE EJECTING SHORTWAVE DYNAMICS SHOULD GRADUALLY ADVANCE
NORTHEAST WITH TIME AND CROSS PORTIONS OF FAR WESTERN
KS...NORTHEAST CO...FAR WESTERN NE AND SOUTHEAST WY THROUGH THE
EVENING HOURS.

THE LAST COUPLE OF HRRR RUNS SUGGEST THE POTENTIAL FOR CONVECTION
TO BECOME LOCALLY FOCUSED AND SLOW-MOVING...ESPECIALLY ACROSS FAR
SOUTHEAST WY. A COUPLE OF CELL-MERGERS WILL BE POSSIBLE AS WELL.
MANY AREAS OF ESPECIALLY NORTHEAST CO AND SOUTHEAST WY HAVE BEEN
VERY WET OF LATE...AND THE LATEST HRRR SUGGESTS ADDITIONAL
RAINFALL AMOUNTS THIS EVENING OF 1 TO 3 INCHES WITH ISOLATED
HEAVIER AMOUNTS. THE LOCALLY SLOW MOVEMENT TO THE ACTIVITY WILL
FAVOR A RISK OF FLASH FLOODING. EXPECT THE CONVECTION TO WEAKEN
WITH THE LOSS OF DIURNAL HEATING AFTER ABOUT 03Z.

ORRISON

ATTN...WFO...BOU...CYS...DDC...GLD...LBF...PUB...

ATTN...RFC...ABRFC...MBRFC...

LAT...LON   42330485 42050331 41620230 40430112 38880075 
            37470132 37060214 37050319 37170367 37860377 
            38820361 39520374 40190418 40670516 41160592 
            41810637 42270615