MESOSCALE PRECIPITATION DISCUSSION 0262
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1118 PM EDT MON MAY 22 2017

AREAS AFFECTED...CENTRAL NC

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

VALID 230317Z - 230747Z

SUMMARY...AN UPTICK IN CONVECTION MAY LEAD TO A FEW FLASH FLOOD
CONCERNS OVER CENTRAL NC FOR THE NEXT SEVERAL HOURS...ESPECIALLY
IN URBAN AREAS AND AREAS OF LOWER FLASH FLOOD GUIDANCE.

DISCUSSION...SCATTERED CONVECTION CONTINUES THIS EVENING ACROSS
PORTIONS OF NORTH CENTRAL NORTH CAROLINA. DECOUPLING AFTER SUNSET
HAS PROBABLY RESULTED IN A SLIGHT MOISTENING OF THE LOW
LEVELS...WITH A SMALL INCREASE IN EASTERLY 925MB FLOW ABOVE THE
INVERSION NEAR THE BACKDOOR FRONT. THESE FACTORS MAY ALLOW
CONVECTIVE ACTIVITY TO PERSIST FOR THE NEXT SEVERAL HOURS. FORCING
AND FLOW IS WEAK...SO NOT EXPECTING MUCH ORGANIZATION. SHOULD
STILL SEE SLOW MOVING STORMS PULSING UP AND REFORMING ALONG
OUTFLOWS CONSOLIDATING INTO THE REMAINING MUCAPE MAX OF 1000 J/KG
OVER NORTH CENTRAL NC.

LIKELY THAT STORMS WILL BE PRETTY EFFICIENT RAINFALL
PRODUCERS...WITH PWAT VALUES INCREASING ABOVE 1.5" AND STORMS
GENERALLY LOW TOPPED AND WARM PROCESS DOMINATED. THE LACK OF
ORGANIZATION SHOULD LIMIT RAINFALL TOTALS...HOWEVER THE EFFICIENT
ENVIRONMENT STILL SUPPORTS SOME 1-2" IN AN HOUR AMOUNTS AND
ISOLATED 2-4" TOTALS...WHICH MAY BEGIN TO EXCEED SOME OF THE LOWER
FLASH FLOOD GUIDANCE OVER PORTIONS OF CENTRAL NC. FOR THIS REASON
A FEW FLASH FLOOD ISSUES ARE POSSIBLE OVER THE NEXT SEVERAL
HOURS...WITH ACTIVITY EVENTUALLY DIMINISHING AS CAPE GETS ERODED
WITH TIME. THE EVOLUTION DEPICTED BY THE 00Z EXPERIMENTAL HRRR IS
THE CLOSEST FIT TO OUR EXPECTATIONS AT THIS TIME.

CHENARD

ATTN...WFO...GSP...RAH...RNK...

ATTN...RFC...SERFC...

LAT...LON   36408036 36117887 35757824 35437783 35187843
            35287970 35458060 35648135 35788156 36248083