MESOSCALE PRECIPITATION DISCUSSION 0413
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
923 AM EDT FRI JUL 06 2018

AREAS AFFECTED...KANSAS...OKLAHOMA PANHANDLE

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

VALID 061321Z - 061830Z

SUMMARY...THUNDERSTORMS WERE DEVELOPING EARLY THIS MORNING ACROSS
PORTIONS OF KANSAS...AND THESE STORMS WERE MOVING VERY SLOWLY.
HEAVY RAINFALL AND LOCALIZED FLASH FLOODING WILL BE POSSIBLE.

DISCUSSION...CONVECTION HAS BLOSSOMED OVER THE PAST COUPLE HOURS
(11-13Z) IN AN ARC ROUGHLY NEAR THE I-70 CORRIDOR IN NORTH-CENTRAL
KANSAS. THE GOES-16 CLOUD TOP HEIGHT PRODUCT HAS BEEN INDICATING
CONVECTION STEADILY BECOMING DEEPER...AND THIS MATCHES CLOSELY
WITH THE IR TREND OF COOLING CLOUD TOPS AND AN INCREASE IN
LIGHTNING ACTIVITY. FURTHER TO THE SOUTHWEST...IN SOUTHWEST KANSAS
AND THE OKLAHOMA PANHANDLE...MORE ISOLATED THUNDERSTORMS WERE
LINGERING IN THE MOIST AIR MASS...PARTICULARLY IN THE VICINITY OF
A NEARLY STATIONARY MCV IN THE CENTRAL OKLAHOMA PANHANDLE. THE
VAST MAJORITY OF THE CELLS IN THIS REGION APPEARED TO BE MOVING
SLOWER THAN 10 KNOTS...AND RAP FORECAST CORFIDI VECTORS THROUGH
18Z ACROSS THE REGION ARE GENERALLY 5 KNOTS OR LESS WITH THE
CENTER OF A MID-UPPER LEVEL RIDGE AXIS IN THE AREA.

STRONG FORCING FOR FOCUSED ASCENT DOES NOT EXIST ACROSS THE
REGION...AND LOW-LEVEL INFLOW IN THE 925MB LAYER IS ONLY AROUND
10-15 KNOTS OUT OF THE EAST. THIS MAY PREVENT CONVECTION FROM
SUSTAINING IN A PARTICULAR LOCATION FOR AN EXTENDED PERIOD OF
TIME...BUT GIVEN THE SLOW STORM MOTIONS...SOME LOCATIONS WILL
LIKELY RECEIVE 60-90 MINUTES OF NEARLY UNINTERRUPTED HEAVY RAIN.
THIS COULD PRODUCE LOCALIZED AREAS OF SEVERAL INCHES OF RAIN IN
JUST OVER AN HOUR...AND A REPORT OF THESE TYPE OF RAIN RATES WAS
RECENTLY RECEIVED FROM NEAR SALINA KS. DUAL POL AND MRMS RAINFALL
ESTIMATES HAVE BEEN AROUND 2 IN/HR IN THE VICINITY OF SOME OF THE
STRONGER CONVECTION...AND THIS MAY CONTINUE INTO THE MORNING
HOURS. THE 12Z DDC SOUNDING SHOWED AROUND 2000 J/KG OF UNINHIBITED
CAPE AND PRECIPITABLE WATER VALUE OF 1.86 INCHES. THIS IS AMONG
THE HIGHER OBSERVED PWAT VALUES AT DDC AND PWATS AROUND KANSAS ARE
GENERALLY ABOVE THE 90TH PERCENTILE. THIS ENVIRONMENT SHOULD
ENABLE VERY HEAVY RAIN RATES.

A MARGINAL RISK AREA WILL ALSO BE ADDED ON THE DAY 1 EXCESSIVE
RAINFALL OUTLOOK FOR PORTIONS OF THIS REGION.

LAMERS

ATTN...WFO...AMA...DDC...GID...GLD...ICT...PUB...TOP...

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

LAT...LON   39689941 39229727 38419611 37779723 37869896
            37379998 36560095 36480196 37330214 38160121
            38870135 39460105