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 231901 AFDRLX Area Forecast Discussion National Weather Service Charleston WV 301 PM EDT Sun Apr 23 2017 .SYNOPSIS... Upper level low passes to our south tonight and then swings east to the Carolina coastal states Monday, keeping rain mainly in the south and east through Monday. Warmer midweek before a cold front crosses Thursday night. && .NEAR TERM /THROUGH MONDAY/... As of 200 PM Sunday... While there are typical model differences in the exact handling of the broad upper low currently over the western Tennessee valley this period, all are indicating SIMILAR main effects for our area. The associated rain shield just over our southern most zones early this afternoon will struggle to shift northward this afternoon and evening. As the upper low slides south southeast into the southeastern states tonight, the rain shield will tend to shift slowly eastward and spread up the WV mountains. This process will continue Monday as the upper low then reaches the Southeast coast. By Monday afternoon, most of the rain will have shifted into the mountains. Thus, will keep the northwest half basically dry and the southeast quite wet, with a tight POP gradient in between. In addition, the good influx of moisture and steady but persistent rain over the southern mountains will validate continuing the Flood Watch as is, with flood warnings already in effect for SW VA. The watch may very well have to be extended and expanded up the mountains later tonight and Monday, but there is enough uncertainty in the exact track of the upper low and the axis of heavy rain for further evaluation. Otherwise, look for coolest temps tonight and warmest temps Monday over northwest portions of the area given less thick clouds and lack of rain. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... As of 245 PM Sunday... Influences from the cut off upper low over the Southeast will continue through Tuesday as an inverted trough remains over the area. Precipitation chances will largely be confined to the eastern half of the CWA, while the low and mid level moisture starts to dissolve CWA wide after Tuesday. Improvements expected all around with temperatures on the increase, and the far southern zones drying out after a few days of persistent rain. Expecting a significant increase in 500mb heights heading into Wednesday, and an 850mb temperature jump of 5-8C. In the meantime, the upper trough merger over the central states will be occurring. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... As of 245 PM Sunday... Getting quick cyclogenesis occurring with the upper trough merger over the Midwest, and a strong frontal system deepening into the western Great Lakes. The models continue to take it towards northern Ontario, so the cold front is still expected to shear out considerably as it passes through the Ohio Valley. Still needing POPs into Thursday, with thunder, but overall it should be a weakening cold front as it affects our area. Strong upper level ridge builds over the southeastern states while a southern plains upper low deepens, developing another surface low. Warm frontal influences keep low end chances for precipitation into the weekend, but the temperature trend continues to go upwards, with summer like readings prevailing. && .AVIATION /19Z SUNDAY THROUGH FRIDAY/... 18Z Sunday thru 18Z Monday... As of 1145 AM Sunday... Quite a gradient of Flight Categories this period. Upper level low currently centered over the Tennessee Valley will slowly drop south and east this afternoon and tonight. However, it is broad enough to pull deeper moisture and widespread rain northward into parts our area this afternoon and tonight. Northern edge of rain by 00Z will be just south of HTS-CRW-W22 line with the south quite wet and the north remaining dry. Tonight will see this rain shield shift toward the east and expand up eastern WV, with the back edge of the rain mainly along and east of a CRW-CKB line by 14Z. Look for VFR ceilings to mostly persist outside of the precip shield this period, mainly at PKB and CKB. Mostly MVFR/IFR IN the precip shield, with MVFR prevailing at HTS,CRW, and possibly EKN. IFR/LIFR in the southern and central mountains including BKW. Wind will be easterly at 5 to 10 KTS, except 10 to 20 KTS higher mountain elevations. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z MONDAY... FORECAST CONFIDENCE: Low to Medium. ALTERNATE SCENARIOS: A minor shift in the upper low movement may greatly affect timing and development of rain across the area. 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 M M M M M M M M M M M L HTS CONSISTENCY H H M M M M M M M M M L BKW CONSISTENCY L L L L L L L L L L L L EKN CONSISTENCY H H H H H H H H M M M L PKB CONSISTENCY H H H H H H H H H H H M CKB CONSISTENCY H H H H H H H H H H H M AFTER 18Z MONDAY... IFR possible into Monday with another wave of low pressure. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...Flash Flood Watch until midnight EDT tonight for WVZ033-034. OH...None. KY...None. VA...Flash Flood Watch until midnight EDT tonight for VAZ003-004. && $$ SYNOPSIS...JMV/26 NEAR TERM...JMV SHORT TERM...26 LONG TERM...26 AVIATION...JMV is the U.S. government's official web portal to all federal, state and local government web resources and services.