Area Forecast Discussion
Issued by NWS Charleston, WV

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 50
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KRLX 251911 AFDRLX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHARLESTON WV 311 PM EDT MON APR 25 2016 .SYNOPSIS... COLD FRONT SINKS SOUTH TUESDAY...MOVES INTO CWA DURING TUESDAY NIGHT. FRONT WAFFLES BACK/FORTH IN OUR VICINITY THROUGH THURSDAY NIGHT. BOUNDARY PROVIDES OPPORTUNITIES FOR ROUNDS OF SHOWERS/STORMS. && .NEAR TERM /THROUGH TUESDAY/... AS OF 18Z...HOURLY TEMPERATURES APPEAR ON TRACK...WITH THE WARMEST LATE TODAY IN THE DRIEST CORRIDOR...INCLUDING CRW. MARGINAL LOW LEVEL MOISTURE OVERNIGHT FOR PATCHES OF 4 TO 7 THSD FT CLOUDS TO LINGER AT TIMES. WITH 925 MB FLOW AT 06Z AROUND 30 KNOTS...LIKED OUR PREVIOUS MINIMUM TEMPERATURES...WHICH IS MOSTLY ON THE HIGHER SIDE OF GUIDANCE. MOISTURE DEEPENS 12Z TO 18Z...SO SCATTERED AREAS OF SHOWERS POSSIBLE TUESDAY MORNING INTO THE AFTERNOON WELL SOUTH OF THE FRONTAL BOUNDARY. STAYED AOA MAXIMUM TEMPERATURES...HOPING FROM SOME BREAKS IN THE CLOUDS. GLOBAL MODELS LESS VIGOROUS WITH CONVECTION NEAR THE FRONT LATE TUESDAY. WE STAYED WITH THE THEME...THAT MORE CONVECTION FORMS NEAR THE FRONT AND AFFECTS NORTHERN COUNTIES LATE IN THE DAY...WHICH IS MORE TOWARD THE 12Z NAM SOLUTION. LOW CONFIDENCE THOUGH IN THE THE AMOUNT OF RAIN. INFLOW AREA TO THE WEST HAS PRECIPITABLE WATER ABOUT 1.25 INCHES. COULD NOT RULE OUT SOME WNW TO ESE TRAINING. OVERALL...AT THIS DISTANCE WILL GO WITH LESS THAN A HALF INCH BY 00Z IN THE NORTH...LESS THAN A QUARTER IN THE SOUTH BY 00Z WEDNESDAY. BASING FORECAST ON FRONT JUST ENTERING OUR PERRY AND MORGAN COUNTIES BY 23Z TUESDAY...AND NEARING MGW IN NRN WEST VIRGINIA. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
-- Changed Discussion --
THERE IS MUCH MODEL DISCREPANCY IN THE MASS AND QPF FIELDS THIS PERIOD...AS THE INTERACTION BETWEEN THE NORTHERN STREAM FLOW ACROSS THE GREAT LAKES AND NEW ENGLAND AND THE CLOSED UPPER LOW OVER THE PLAINS STATES IS UNCERTAIN. CONFIDENCE IN TIMING...ESPECIALLY LATER IN THE PERIOD IS RATHER LOW. WHILE MODELS AGREE THERE WILL BE ENOUGH PUSH OF THE COLD FRONT SOUTHWARD INTO THE AREA TUESDAY NIGHT...HOW FAR SOUTH IT GETS BEFORE STALLING IS A BIG QUESTION. IN ADDITION... WHEN AND HOW FAST THE FRONT THEN RETURNS NORTHWARD AS A WARM FRONT AS THE UPPER LOW TO THE WEST STARTS EJECTING EASTWARD IS ALSO A QUESTION. THE BEST SOLUTION AT THIS TIME IS TO TAKE A BLEND OF THE SOLUTIONS. THIS ACCEPTED SOLUTION WILL BRING ABOUT A WET PERIOD WITH THE FRONT BASICALLY HANGING AROUND THE AREA. GOOD INSTABILITY IS SHOWN WITH THE FRONT...SO THUNDER INCLUDED MOST AREAS MOST OF THE TIME...BUT TOO EARLY TO MENTION OTHER THAN GENERAL THUNDER. SPECIFICALLY...WE HAVE THE FRONT AT THE BEGINNING OF THE PERIOD IN FAR NORTHERN ZONES...DROPPING SOUTH INTO THE SOUTHERN COAL FIELDS BEFORE STALLING TUESDAY NIGHT. THE FRONT WILL THEN START TO RETURN SLOWLY NORTHWARD LATER WEDNESDAY AHEAD OF THE EJECTING UPPER LOW...LIFTING NORTH OF THE AREA DURING THURSDAY. BEST POPS/QPF WILL THEN ACCOMPANY THE FRONT FROM NORTH TO SOUTH TUESDAY NIGHT...LESSENING SOMEWHAT BEFORE THE FRONT RETURNS NORTHWARD LATE WEDNESDAY INTO THE THURSDAY MORNING. THURSDAY AFTERNOON SHOULD PLACE US IN THE WARM SECTOR... BUT STILL A LOWER CHANCE OF SHOWERS AND STORMS THURSDAY AFTERNOON GIVEN THE CONTINUING INSTABILITY. AT THIS TIME WE HAVE NO HAZARDOUS WEATHER MENTIONED FOR THIS PERIOD. TEMPERATURES WOULD HIGHLY DEPEND ON THE CLOUDS AND SHOWERS. DESPITE GOING WITH GENERALLY UNSETTLED WEATHER AND CLOUDS...WE LOOK FOR HIGHS SLIGHTLY ON THE HIGHER SIDE OF GUIDANCE BY DAY AND ON THE HIGHER SIDE BY NIGHT.
-- End Changed Discussion --
&& .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
-- Changed Discussion --
MODELS IN AGREEMENT WITH LOW PRESSURE MOVING THROUGH THE AREA ON FRIDAY AND EXITING OFF THE ATLANTIC COAST LATE FRIDAY NIGHT. ANY SHOWERS WILL EXIT WITH THIS SYSTEM. SATURDAY LOOKS TO BE THE BEST DAY OUT OF THE WEEKEND WITH WEAK RIDGING TAKING HOLD. SUNDAY THROUGH MONDAY IS WHERE THE CONFIDENCE OF THE FORECAST DIMINISHES. BOTH THE GFS AND ECMWF DEVELOP SYSTEM OUT TO OUR WEST, BUT TIMING AND POSITION OF THE SYSTEMS DIFFER. THE GFS BRINGS A WARM FRONTAL BOUNDARY UP ACROSS THE AREA AND DEVELOPS A LOW PRESSURE SYSTEM THAT TRACKS ACROSS THE SOUTHERN PORTION OF THE CWA. THE ECMWF DEVELOPS THE LOW AND TRACKS IT NORTH OF THE CWA THROUGH MONDAY. IN ANY CASE THERE WILL BE SHOWERS AROUND. WITH THIS SCENARIO, INTRODUCE LIKELY POPS OVER MUCH OF THE AREA ON SUNDAY AND KEPT CHC POPS EVERYWHERE MONDAY.
-- End Changed Discussion --
&& .AVIATION /19Z MONDAY THROUGH SATURDAY/... LOWERED CONFIDENCE TO MEDIUM...IN TRYING TO FIGURE COVERAGE OF MOSTLY SHOWERS WELL SOUTH OF THE FRONT...12Z TO 21Z TUESDAY...BEFORE ANY STRONGER CONVECTION FORMS NEAR THE FRONT...AND SINKS SOUTH LATE IN THE DAY ON TUESDAY. HAVE AREAS OF SCATTERED TO BROKEN CLOUDS AT 4 TO 7 THSD FT AGL OVERNIGHT. LOW LEVEL FLOW AT 925 MB INCREASES TO NEAR 30 KNOTS BY 06Z TUESDAY AND REMAINS THROUGH 12Z...SO KEPT WINDS STIRRING AT THE SURFACE. WITH THE MILDER TEMPERATURES...NO FOG. WILL HAVE SOME 5 MILES IN SCATTERED SHOWERS POSSIBLE WORKING INTO WESTERN COUNTIES BY 12Z AND SPREADING EAST DURING THE DAY. THUNDERSTORMS COULD BE MORE LIKELY AFTER THE 18Z TAF PERIODS ENDS... FOR LATE AFTERNOON...ESPECIALLY CLOSER TO THE FRONT. FIGURE THE FRONT WILL BE NEAR MGW TO LHQ BY 23Z TUE -00Z WED. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z TUESDAY... FORECAST CONFIDENCE: MEDIUM. ALTERNATE SCENARIOS: COVERAGE OF SHOWERS COULD BE MORE THAN EXPECTED BY 18Z TUESDAY. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05 EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01 CRW CONSISTENCY H H H H H H H H H H H H HTS CONSISTENCY H H H H H H H H H H H H BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY H H H H H H H H H H H H PKB CONSISTENCY H H H H H H H H H H H H CKB CONSISTENCY H H H H H H H H H H H H AFTER 18Z TUESDAY... IFR POSSIBLE IN ROUNDS OF SHOWERS OR STORMS TUESDAY NIGHT THROUGH THURSDAY. LOW CEILINGS MAY ALSO FORM WEDNESDAY MORNING NORTH OF THE STALLED FRONT. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...JS/KTB/JMV NEAR TERM...KTB SHORT TERM...JMV LONG TERM...JS AVIATION...KTB

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