500  
FXUS61 KRNK 171838  
AFDRNK  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE BLACKSBURG VA  
238 PM EDT SUN JUN 17 2018  
   
SYNOPSIS
 
 
UPPER LEVEL RIDGING WILL CONTINUE TO BUILD INTO THE AREA  
THROUGH EARLY NEXT WEEK BRINGING A PERIOD OF MAINLY DRY BUT HOT  
WEATHER INTO TUESDAY. A FRONTAL BOUNDARY APPROACHES FROM THE  
NORTH BY MIDWEEK RESULTING IN BETTER CHANCES FOR SHOWERS AND  
STORMS WEDNESDAY AND THURSDAY.  

 
   
NEAR TERM /THROUGH MONDAY/
 
 
AS OF 215 PM EDT SUNDAY...  
 
MID LEVEL WAVE OVER EASTERN WEST VA WILL CONTINUE TO SLIDE SOUTHEAST  
PASSING JUST EAST OF THE MOUNTAINS THIS EVENING. MODELS CONTINUE TO  
SHOW A SPREAD IN CONVECTION FROM THE BLUE RIDGE EAST INTO EARLY THIS  
EVENING BUT OVERALL MOSTLY ISOLATED COVERAGE UNTIL THINGS PERHAPS  
BECOME MORE ORGANIZED TO THE SOUTHEAST OF THE REGION BY EARLY TONIGHT.  
THUS MAINTAINING LOW POPS INTO THIS EVENING WITH BEST CHANCES PIEDMONT  
AND SOUTHERN BLUE RIDGE ESPCLY THE NC MOUNTAINS WHERE ONGOING INSTABILITY  
REMAINS HIGHEST.  
 
WAVE EXITS OVERNIGHT ALLOWING UPPER RIDGING TO EDGE A BIT EASTWARD AS  
500 MB HEIGHTS BUILD EAST BEHIND THE EXITING SHORTWAVE. THIS SHOULD  
ALLOW ANY ONGOING ISOLATED CONVECTION TO FADE OVERNIGHT WITH PATCHY FOG  
AND PERHAPS SOME LOW CLOUDS ESPCLY EAST WHERE ANY SHOWERS OCCURRED.  
OTHERWISE MAINLY CLEAR BUT QUITE MUGGY WITH LOWS EVEN MILDER THAN  
LAST NIGHT PER MID/UPPER 60S MOUNTAINS TO AROUND 70 EAST.  
 
MID/UPPER RIDGE STRENGTHENS OVER THE AREA ON MONDAY WITH ANY ADDED  
SHORTWAVE ENERGY RIDING IN FROM THE NORTHWEST QUITE WEAK AND FARTHER  
EAST THAN TODAY. ALSO SEEING SOME SLIGHT WARMING/DRYING ALOFT AS  
SUBSIDENCE LOOKS STRONGER DESPITE QUITE A MOIST LOW LEVEL ENVIRONMENT  
CHARACTERIZED BY HIGH INSTABILITY UNDER WEAK FLOW ALOFT. LATEST  
GUIDANCE ALSO SHOWING LESS CONVECTION GIVEN LIMITED FOCUS WITH MAIN  
COVERAGE DRIVEN BY OROGRAPHICS AND DIFFERENTIAL HEATING PER WEAK  
WEST/NORTHWEST BOUNDARY LAYER FLOW. THIS SUPPORTS MAINLY ISOLATED  
CONVECTION AT BEST MOUNTAINS, ESPCLY BLUE RIDGE, SO RUNNING WITH SPOTTY  
20/30 POPS AND MAINLY SUNNY ELSEWHERE. HEAT AND HUMIDITY THE MAIN  
CONCERNS WITH HIGHS LIKELY REACHING THE MID 90S PIEDMONT AND 85-90  
ELSEWHERE OUTSIDE OF THE HIGHER ELEVATIONS. HOWEVER AGAIN APPEARS THAT  
WEAK DOWNSLOPING MAY BE ENOUGH TO KEEP DEWPOINTS IN CHECK WITH  
SUBSEQUENT HEAT INDEX VALUES BELOW 105. THUS OPTING TO HOLD OFF ON  
HOISTING HEAT ADVISORY HEADLINES OUT EAST FOR NOW WHILE MAINTAINING  
MENTION IN THE HWO.  

 
   
SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/
 
 
AS OF 200 PM EDT SUNDAY...  
 
A VERY WARM UPPER RIDGE WILL BE OVER THE SOUTHEASTERN US ON TUESDAY.  
LIGHT SOUTHWEST FLOW AT THE SURFACE WILL HELP PUMP MOISTURE INTO THE  
APPALACHIANS AND CENTRAL MID ATLANTIC REGION. THIS WILL RESULT IN  
HOT AND HUMID CONDITIONS WITH HIGH HEAT INDEX VALUES. HIGH  
TEMPERATURES TUESDAY WILL BE IN THE MID TO UPPER 90S EAST OF THE  
BLUE RIDGE WITH HEAT INDEX VALUES OVER 100. HIGHS WEST OF THE RIDGE  
WILL GENERALLY BE IN THE MID TO UPPER 80S WITH HEAT INDEX VALUES IN  
THE MID 80S TO LOWER 90S.  
 
CONVECTION TUESDAY AFTERNOON AND EVENING WILL PRIMARILY BE OVER THE  
MOUNTAINS AND DRIVEN BY DIFFERENTIAL HEATING, BUT SHORT-LIVED WITH A  
MID-LEVEL RIDGE ALSO OVER THE REGION. A FEW STORMS MAYBE ABLE TO  
PRODUCE DAMAGING WINDS AS THEY DECAY DURING THE EVENING. THERE IS A  
CHANCE OUTFLOW DRIVEN THUNDERSTORMS COULD TRACK ACROSS A LINE NORTH  
OF LEWISBURG WV TO LYNCHBURG VA AS A WAVE MOVES ALONG A STALLED  
BOUNDARY ALONG THE MASON-DIXON LINE. MODELS HAVE A WAVE TRACKING  
FROM CINCINNATI TO PITTSBURGH IN THE AFTERNOON, THEN DIVING SOUTH  
TOWARDS RICHMOND AND NORFOLK IN THE EVENING.  
 
THE UPPER LEVEL RIDGE SINKS SOUTH ON WEDNESDAY WHICH COULD SEND A  
COLD FRONT FROM THE GREAT LAKES TOWARDS THE REGION WEDNESDAY  
AFTERNOON AND NIGHT. BOTH THE GFS AND ECM HAVE A WAVE TAKING A  
SIMILAR TRACK TO THE ONE TUESDAY, FROM CINCINNATI TO PITTSBURGH THEN  
DIVING SOUTH TOWARDS RICHMOND AND NORFOLK. THIS AGAIN WILL LEAVE THE  
AREA IN A MOSTLY DIFFERENTIAL HEATING DRIVEN STORMS ENVIRONMENT  
CONFINED MAINLY TO THE MOUNTAINS WITH OUTFLOW DRIVEN STORMS ALONG A  
LINE NORTH OF LEWISBURG WV TO LYNCHBURG VA. THE ONLY DIFFERENCE  
NOTED FOR WEDNESDAY WILL BE MORE AREAL COVERAGE OF STORMS ACROSS THE  
MOUNTAINS.  
 
HIGH TEMPERATURES WEDNESDAY MAY BE SLIGHTLY COOLER WITH DEBRIS  
CLOUDS HANG OVER THE AREA, BUT IT WILL STILL BE WARM AND HUMID.  
HIGHS WEDNESDAY WILL BE IN THE LOWER TO MID 90S EAST OF THE BLUE  
RIDGE WITH HEAT INDEX VALUES NEAR 100. HIGHS WEST OF THE RIDGE WILL  
GENERALLY BE IN THE MID TO UPPER 80S WITH HEAT INDEX VALUES IN THE  
MID 80S TO LOWER 90S.  

 
   
LONG TERM /THURSDAY THROUGH SUNDAY/
 
 
AS OF 200 PM EDT SUNDAY...  
 
MODEL UNCERTAINTY LEADS TO A LOW CONFIDENCE IN THE LONG-TERM  
FORECAST. THE MAIN DIFFERENCE WITH THE GFS AND THE ECM IS TIMING  
WITH THE GFS BEING A DAY FASTER THAN THE ECM. THIS WILL AFFECT  
TEMPERATURES AND WHEN/IF STRONG TO SEVERE WEATHER WILL COME ACROSS  
THE AREA.  
 
THE GFS SENDS A COLD FRONT INTO THE AREA, STALLING IT FROM LEWISBURG  
WV TO DANVILLE VA BY THURSDAY MORNING. A WAVE COMING AROUND THE  
UPPER LEVEL RIDGE, NOW OVER THE FLORIDA PANHANDLE, TRACKS ALONG THE  
FRONT AND BRINGS THE CHANCE FOR STRONG THUNDERSTORMS FROM BLUEFIELD  
WV TO RALEIGH NC SOUTH THURSDAY AFTERNOON AND NIGHT. FOLLOWING THIS  
CONVECTION, THE FRONT SINKS SOUTH INTO NORTH CAROLINA WITH A WEAK  
INSITU WEDGE OVER THE AREA FRIDAY. THE GFS BREAKS THE WEDGE ON  
SATURDAY WITH A WEAK FRONTAL PASSAGE SATURDAY NIGHT.  
 
THE ECM KEEPS THE FRONT TO OUR NORTH THURSDAY WITH A WAVE TRACKING  
FROM PITTSBURGH PA TO NORFOLK VA. THE ECM HAS THIS FRONT BISECTING  
THE AREA FRIDAY WITH STRONG CONVECTION FROM BLUEFIELD WV TO RALEIGH  
NC FRIDAY AFTERNOON AND NIGHT. THE ECM ALSO HAS A TROPICAL SYSTEM  
OFF THE TEXAS COAST THURSDAY, WHICH MAY STRENGTHEN THE RIDGE  
ALLOWING FOR THE DELAY IN BRINGING THE FRONT INTO THE REGION. THE  
ECM HAS AN INSITU WEDGE OVER THE REGION SATURDAY ERODING IT WITH A  
FRONTAL PASSAGE ON SUNDAY.  

 
   
AVIATION /18Z SUNDAY THROUGH FRIDAY/
 
 
AS OF 1230 PM EDT SUNDAY...  
 
WEAKENING COMPLEX OF SHOWERS JUST NORTH OF KLWB WILL CONTINUE TO  
SLIDE ALONG THE INTERSTATE 64 CORRIDOR NEAR KHSP OVER THE NEXT  
HOUR BEFORE FADING. HOWEVER EXPECTING ADDED AT LEAST ISOLATED  
SHOWERS AND STORMS TO REDEVELOP SOUTH OF THE ASSOCIATED RESIDUAL  
CLOUD CANOPY WITH PERHAPS SOME OF THIS COVERAGE AFFECTING KLYH  
BY MID AFTERNOON AND SOUTH TO KDAN BY LATE IN THE DAY. THEREFORE  
MAY INCLUDE A VCSH/VCTS MENTION AT THESE SITES. ALSO CANT  
TOTALLY RULE OUT AN ISOLATED SHOWER POPPING UP AROUND KLWB/KROA  
BUT WONT INCLUDE ANYTHING MORE THAN BROKEN VFR CIGS THERE  
THROUGH EARLY THIS EVENING. OTHERWISE VFR OUTSIDE OF ANY  
CONVECTION INTO EARLY TONIGHT. WINDS SHOULD BE LIGHT BUT GUSTY  
FROM THE NORTH AND WEST NEAR ANY SHOWERS OR STORMS.  
 
AFTER MIDNIGHT, SHOULD SEE LESS CLOUDS, INCREASED HUMIDITY AND  
CALM WINDS. APPEARS FOG WILL FORM IN THE VALLEYS, AND MAINTAINED  
MVFR AT ALL BUT KROA/KBLF, WITH IFR AT KLWB.  
 
HIGH PRESSURE WILL CONTINUE TO STRENGTHEN OVER THE REGION EARLY  
NEXT WEEK WITH OVERALL VFR CONDITIONS REMAINING IN PLACE  
MONDAY INTO MONDAY NIGHT WITH CONVECTION QUITE ISOLATED AT BEST.  
 
CONFIDENCE IS MEDIUM ON FOG FORMATION, BUT LOW FOR HOW LOW  
VISIBILITIES DROP.  
   
EXTENDED AVIATION DISCUSSION
 
 
HIGH PRESSURE LOOKS TO MAINTAIN CONTROL NOW INTO TUESDAY WITH  
MOST SHOWERS AND STORMS STAYING JUST NORTH AND WEST OF THE  
REGION UNTIL PERHAPS TUESDAY EVENING OR NIGHT. AN APPROACHING  
COLD FRONT FROM THE NORTHWEST MAY FINALLY ERODE THE RIDGE ENOUGH  
TO ALLOW FOR BETTER COVERAGE OF CONVECTION ACROSS THE NORTH ON  
WEDNESDAY AND OVER THE SOUTHERN AND WESTERN SECTIONS INTO  
THURSDAY. OTHERWISE OVERALL VFR EXPECTED OUTSIDE ANY STORMS.  
 
LIKELY TO SEE A CONTINUATION OF LATE NIGHT VISIBILITY  
RESTRICTIONS DUE TO FOG ACROSS THE MOUNTAIN VALLEYS IMPACTING  
LOCATIONS LIKE KLWB/KBCB, BUT FOR ONLY A FEW HOURS AROUND  
DAYBREAK EACH MORNING NEXT WEEK.  
 

 
   
CLIMATE
 
 
AS OF 200 PM EDT SATURDAY...  
 
RECORD HIGHS RECORD WARM MINS  
 
JUNE 17  
BLUEFIELD WV 92 IN 1952 62 IN 2003  
DANVILLE VA 99 IN 1981 62 IN 1965  
LYNCHBURG VA 96 IN 1944 73 IN 1939  
ROANOKE VA 96 IN 1944 74 IN 1912  
BLACKSBURG VA 88 IN 1994 67 IN 2015  
 
JUNE 18  
BLUEFIELD WV 92 IN 1944 60 IN 1927  
DANVILLE VA 98 IN 1944 69 IN 1979  
LYNCHBURG VA 96 IN 1944 71 IN 1925  
ROANOKE VA 97 IN 1925 73 IN 1921  
BLACKSBURG VA 88 IN 2014 65 IN 2004  
 
JUNE 19  
BLUEFIELD WV 91 IN 1905 66 IN 1920  
DANVILLE VA 102 IN 1944 70 IN 1968  
LYNCHBURG VA 97 IN 1944 73 IN 1925  
ROANOKE VA 97 IN 1944 73 IN 2014  
BLACKSBURG VA 89 IN 1984 65 IN 2015  
 
JUNE 20  
BLUEFIELD WV 91 IN 1952 57 IN 1920  
DANVILLE VA 102 IN 1933 65 IN 1956  
LYNCHBURG VA 99 IN 1964 74 IN 1924  
ROANOKE VA 101 IN 1931 76 IN 2009  
BLACKSBURG VA 90 IN 1994 68 IN 2009  
 

 
   
EQUIPMENT
 
 
AS OF 215 PM EDT THURSDAY...  
 
THE NOAA WEATHER RADIO TRANSMITTER IN HINTON, WEST VIRGINIA THAT  
IS WXM72 AND BROADCASTING AT A FREQUENCY OF 162.425 MHZ IS OFF  
THE AIR. PARTS ARE ON ORDER TO REPAIR THE TRANSMITTER, BUT THERE  
IS NO KNOWN TIME OF RESTORATION. WE APOLOGIZE FOR ANY  
INCONVENIENCE.  
 

 
   
RNK WATCHES/WARNINGS/ADVISORIES
 
 
VA...NONE.  
NC...NONE.  
WV...NONE.  
 

 
 

 
SYNOPSIS...JH  
NEAR TERM...JH  
SHORT TERM...RCS  
LONG TERM...RCS  
AVIATION...JH/WP  
CLIMATE...RCS  
EQUIPMENT...DS  
 
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