MESOSCALE PRECIPITATION DISCUSSION 0525
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
331 PM EDT MON JUL 23 2018

AREAS AFFECTED...FAR SOUTHERN WY...CO...NORTHERN NM

CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY

VALID 231930Z - 240130Z

SUMMARY...HEAVY SHOWERS AND THUNDERSTORMS WILL BECOME MORE
NUMEROUS THIS AFTERNOON. GIVEN THE INTENSE RAINFALL RATES...SOME
FLASH FLOODING IS EXPECTED.

DISCUSSION...THE LATEST GOES-16 GEOCOLOR RGB IMAGERY SHOWS
CONVECTIVE INITIATION WELL UNDERWAY ACROSS PORTIONS OF FAR
SOUTHERN WY...CENTRAL CO AND NORTHERN NM WITH AN EMPHASIS ON THE
OROGRAPHICALLY FAVORED HIGH TERRAIN. THE LATEST RAP ANALYSIS SHOWS
PLENTY OF DIURNALLY ENHANCED INSTABILITY BANKING UP ACROSS THE
HIGH PLAINS AND OVER THE HIGH TERRAIN...WITH MLCAPE VALUES LOCALLY
EXCEEDING 1500 J/KG. THIS WILL COUPLE WITH AN ANOMALOUSLY MOIST
ENVIRONMENT ALONG A FRONTAL ZONE TO SUSTAIN AND EXPAND THE
CONVECTIVE THREAT GOING THROUGH THE AFTERNOON HOURS ACROSS THE
REGION.

THE PWATS ACROSS EASTERN CO IN VICINITY OF THE FRONT ARE AROUND
1.2 TO 1.4 INCHES WHICH IS A SOLID 2+ STANDARD DEVIATIONS ABOVE
NORMAL. THIS WILL ALLOW THE CONVECTION TO BE RATHER EFFICIENT AND
CAPABLE OF PRODUCING ENHANCED RAINFALL RATES OVER THE NEXT SEVERAL
HOURS. THE LATEST HIRES CAM GUIDANCE SUGGESTS CONVECTION WILL
INITIALLY BE ANCHORING OVER THE HIGH TERRAIN...WITH SOME FAVORED
LOCATIONS INCLUDING THE SAN JUAN MOUNTAINS OF SOUTHWEST CO AND THE
SANGRE DE CRISTO RANGE OF NORTHERN NM. HOWEVER...THE CONVECTION
WILL BE FOCUSING ALONG AND JUST WEST OF THE FRONT RANGE EXTENDING
AS FAR NORTH AS FAR SOUTHERN WY.

GRADUALLY THE CONVECTION TOWARD THE 21Z TO 00Z TIME FRAME WILL
BEGIN TO EDGE OUT INTO THE HIGH PLAINS TO THE EAST OF THE FRONT
RANGE WHERE IT WILL ENCOUNTER MOIST LOW LEVEL EASTERLY FLOW AND A
NOTABLY UNSTABLE BOUNDARY LAYER WHERE MLCAPE VALUES ARE FORECAST
TO BE IN EXCESS OF 2000 J/KG. THIS COUPLED WITH EFFECTIVE BULK
SHEAR VALUES REACHING 30 TO 40 KTS WILL LIKELY HELP FOSTER SOME
ORGANIZED CONVECTION WITH VERY HEAVY RAINFALL RATES.

EXPECT RAINFALL AMOUNTS OF AS MUCH AS 2 TO 4 INCHES TO BE
POSSIBLE...WITH THE HEAVIEST AMOUNTS LIKELY FOCUSING DOWN THE
FRONT RANGE OF CO. THIS WILL LIKELY RESULT IN SOME FLASH
FLOODING...AND AREAS OF THE TERRAIN THAT INCLUDE BURN SCARS WILL
TEND TO BE THE MOST SENSITIVE WHERE RUNOFF WILL BE THE MOST
ENHANCED. WILL CONTINUE TO MONITOR.

ORRISON

ATTN...WFO...ABQ...BOU...CYS...GJT...PUB...

ATTN...RFC...ABRFC...CBRFC...MBRFC...WGRFC...

LAT...LON   41250574 41000495 40400431 39820381 38670322
            37390323 36310376 35790457 35580522 35620564
            35700604 35690659 35960703 36390721 36760766
            37190782 37840783 38460753 39180753 39860733
            40190694 40870646