621  
FXUS61 KRLX 260735  
AFDRLX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE CHARLESTON WV  
335 AM EDT WED APR 26 2017  
   
SYNOPSIS
 
 
COL BETWEEN SYSTEMS GIVES WAY TO SOUTHERLY FLOW TODAY, AHEAD OF  
A COLD FRONT THAT WILL WEAKEN AS IT CROSSES THURSDAY NIGHT.  
WEAK FRONT NORTH THIS WEEKEND. STRONGER COLD FRONT MONDAY.  
 

 
   
NEAR TERM /THROUGH TONIGHT/
 
 
AS OF 330 AM WEDNESDAY...  
 
LIGHT SOUTHERLY FLOW WILL DEVELOP TODAY AND INCREASE A BIT  
TONIGHT, BECOMING A BIT GUSTY ON THE RIDGES. THIS SHOULD BE  
ENOUGH TO PREVENT REDEVELOPMENT OF FOG TONIGHT. SOME MIDDAY CU  
MAY FORM TODAY, AND STRATOCU WILL APPROACH FROM THE WEST TOWARD  
DAWN THURSDAY, AS LOW LEVEL MOISTURE INCREASES WELL AHEAD OF A  
COLD FRONT.  
 
TEMPERATURES CLOSE TO GUIDANCE AND PREVIOUS FORECAST, EXCEPT  
HIGHER ON THE RIDGES TONIGHT.  
 

 
   
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/
 
 
AS OF 330 AM WEDNESDAY...  
 
THUNDERSTORMS WILL DEVELOP ON THURSDAY AS AN UPPER LEVEL TROUGH AND  
SURFACE COLD FRONT MOVE INTO THE REGION. OVERALL, STRONG  
THUNDERSTORM THREAT LOOKING A LITTLE BETTER, WITH STRONG WINDS BEING  
THE PRIMARY HAZARD AS STRONG 60+KT 0-6KM SHEAR AND MODERATE CAPE  
DEVELOPS ACROSS THE REGION. SPC HAS PLACED THE WESTERN 2/3 OF THE  
CWA IN A MARGINAL RISK FOR SEVERE ON THURSDAY. IN ADDITION, HEAVY  
DOWNPOURS WILL ALSO BE A POSSIBILITY WITH ANY THUNDERSTORMS, BUT  
MOISTURE FEED AT THIS POINT DOESNT LOOK TO BE QUITE AS IMPRESSIVE AS  
IN PREVIOUS MODEL RUNS.  
 
COLD FRONTAL BOUNDARY EXITS TO THE EAST OF THE CWA THURSDAY NIGHT,  
WITH DRIER, AND WARM WEATHER TAKING HOLD FOR FRIDAY AS THE FRONTAL  
BOUNDARY GRADUALLY LIFTS BACK NORTH AS A WARM FRONT.  
 

 
   
LONG TERM /SATURDAY THROUGH TUESDAY/
 
 
AS OF 330 AM WEDNESDAY...  
 
FOCUS THIS WEEKEND SHIFTS TO A DEVELOPING AND STRENGTHENING LOW  
PRESSURE SYSTEM ACROSS THE SOUTHERN PLAINS. WARM FRONTAL BOUNDARY  
ACROSS OHIO AT THE START OF THE PERIOD, WITH SHOWERS AND  
THUNDERSTORMS DEVELOPING, SOME OF WHICH COULD BE HEAVY AT TIMES.  
STRONG LOW PRESSURE SYSTEM WILL GRADUALLY MOVE NORTH AND EAST INTO  
THE MIDWEST SUNDAY INTO MONDAY, GRADUALLY SWEEPING A COLD FRONT  
ACROSS THE AREA ON MONDAY. STRONG MOISTURE TRANSPORT INTO THE AREA  
WITH PW VALUES RISING TO 1.2 INCHES OR GREATER, WELL ABOVE NORMAL,  
PARTICULARLY FOR THIS TIME OF YEAR. IN ADDITION, IT WILL BE RATHER  
HOT AND HUMID FOR THIS TIME OF YEAR, WITH DEW POINTS RISING INTO THE  
60S, AND MAX TEMPERATURES IN THE MID TO UPPER 80S FOR MUCH OF THE  
LOWLANDS.  
 

 
   
AVIATION /07Z WEDNESDAY THROUGH SUNDAY/
 
 
AS OF 2 AM WEDNESDAY...  
 
GUIDANCE HAS BACKED OFF ON WIDESPREAD DENSE FOG OVERNIGHT AND  
THIS IS REFLECTED IN THE LATEST SET OF TAFS. STILL HAVE IFR FOG  
10-13Z EXCEPT AN HOUR OR TWO EARLIER IN THE MOUNTAINS. THERE  
WAS A PUBLIC REPORT OF DENSE FOG IN COLVILLE AT 05Z, IN WYOMING  
COUNTY IN SOUTHERN WV.  
 
ONCE THE FOG DISSIPATES AFTER DAYBREAK, VFR CONDITIONS ARE  
EXPECTED.  
 
AFTER A CALM OVERNIGHT, SURFACE FLOW WILL BECOME LIGHT SOUTH  
WEDNESDAY AFTERNOON, AND BECOME A BIT GUSTY ON THE RIDGES  
WEDNESDAY NIGHT. LIGHT WEST TO NORTHWEST FLOW ALOFT OVERNIGHT  
WILL BECOME LIGHT SOUTHWEST ON WEDNESDAY, AND THEN LIGHT TO  
MODERATE SOUTH WEDNESDAY NIGHT.  
 
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z THURSDAY...  
 
FORECAST CONFIDENCE: MEDIUM INTO WEDNESDAY MORNING, THEN HIGH.  
 
ALTERNATE SCENARIOS: DENSE FOG MAY FORM EARLIER AND BECOME MORE  
WIDESPREAD AFTER ALL.  
 
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.  
 
DATE WED 04/26/17  
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17  
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13  
CRW CONSISTENCY H H M M M L L M H H H M  
HTS CONSISTENCY H H H H H M M M H H H M  
BKW CONSISTENCY M M M L L L L L M M H M  
EKN CONSISTENCY H M L L L L L M H H H M  
PKB CONSISTENCY H H M M M L L M H H H M  
CKB CONSISTENCY H H M L L L L M H H H M  
 
AFTER 06Z THURSDAY...  
NO WIDESPREAD IFR CONDITIONS EXPECTED.  
 

 
   
RLX WATCHES/WARNINGS/ADVISORIES
 
 
WV...NONE.  
OH...NONE.  
KY...NONE.  
VA...NONE.  
 

 
 

 
SYNOPSIS...TRM/SL  
NEAR TERM...TRM  
SHORT TERM...SL  
LONG TERM...SL  
AVIATION...TRM  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab WV Page
The Nexlab OH Page
The Nexlab KY Page
The Nexlab VA Page Main Text Page