Area Forecast Discussion
Issued by NWS Blacksburg, VA
Issued by NWS Blacksburg, VA
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970 FXUS61 KRNK 060800 AFDRNK Area Forecast Discussion National Weather Service Blacksburg VA 400 AM EDT Sat Jul 6 2024 .SYNOPSIS... Another very warm and humid day is in store, but temperatures and humidity lower some for the weekend. A cold front moves partially through the area today and will bring a few showers and thunderstorms to the region. These continue mainly south of Highway 460 through the weekend, close to the stalled front. Heavy rain and lightning will be most likely for our North Carolina counties. The front vacillates over the area into next week, and we will see a chance for thunderstorms each day, with temperatures close to normal. && .NEAR TERM /THROUGH SUNDAY/... As of 315 AM EDT Saturday... Key Messages: 1. Heat Advisory issued for parts of the NC and VA Piedmont and Southside VA. Some records may be reached or broken, see Climate section below. 2. A cold front will bring drier air to the mountains beginning this afternoon, limiting showers and thunderstorms to the NC Piedmont and perhaps Pittsylvania, Charlotte, and Halifax in VA. A few showers/isolated thunderstorms were moving across our VA/NC Piedmont along a surface trough, and were remnants of a complex of storms from last night. A cold front was just to our northwest, and will move into our VA Counties around 8 AM. We may see a few showers, but most of the activity will wait until the front reaches a Boone, NC, to Martinsville, VA, to Red Hat, VA line where much juicier air will be. Short wave energy arrives in SW flow later in the afternoon and evening and will impinge on this region. PWATs over the Piedmont where storms are likely will be at least 2.10", while drier air will already be filtering into the mountains north of the front. Last night, GSP`s soundings had 2.22" PWAT, which is extremely high and above climatology. With the front mostly through our forecast area, and instability pooled mostly to our southeast, expect the main concern to be heavy rain leading to flooding along and south of the Boone to Red Hat line mentioned earlier. We already saw some instances of the last night, and with such high moisture content, slow storm motion, and recent rains to boot, it will not take much to have problems. This is suppported by WPC`s Slight Risk for Excessive Rain area. Compressional warming along the front as well as high dew points and continued warmer than normal temperatures (850mb temperatures around 20C) has lead to the need for another Heat Advisory for Buckingham, Appomattox, Campbell, Halifax, Pittsylvania, and Caswell Counties from 11 AM to 8 PM today. Tonight, cooler and drier air continues to filter in, but showers may continue over NC depending on where the front stalls. Where skies clear, expect dense fog, especially in the valleys and where it rains. Confidence in the near term is moderate due to uncertainty in frontal location. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/... As of 1215 PM EDT Friday... Key Messages: 1. A cold front will bring slightly drier air, limiting showers and thunderstorms to areas mainly south of Highway 460. 2. Slightly cooler temperatures expected for this weekend, though these will still be near to slightly above normal. Looking to Saturday night, weather forecast models are in decent agreement that a cold front will make slow progress eastward across central Virginia, where it will gradually stall as it loses its push of cooler drier air from the northwest. Difficult at this point to determine where the front will eventually stall. Regardless, it is expected to remain both close enough and shallow enough to support lingering showers and thunderstorms through Sunday night, mainly for areas to the south of Highway 460. Because of light steering winds, whatever activity that does develop has the potential to produce a few heavy/prolonged downpours that may result in localized flooding issues. Enough dry air will be present north of Highway 460 to limit any coverage of rainfall to isolated pockets at best. By Monday however, the front will begin to lose its characteristics and fade/wash out as low pressure passes across the Great Lakes, dragging another cold front across the lower Ohio River Valley. Southerly wind flow will increase in response to the area of low pressure, carrying deeper moisture from the Gulf of Mexico northward. This will allow for coverage of spotty showers and storms to expand further northward to include southeast West Virginia through the southern Shenandoah Valley. Temperatures will remain near to slightly above normal through the period. && .LONG TERM /WEDNESDAY THROUGH FRIDAY/... As of 1230 PM EDT Friday... Key Messages: 1. Warmer than normal temperatures with daily storms next week. Spotty showers and thunderstorms will develop each afternoon through the middle of the next workweek as a cold front approaches from the west on Tuesday and eventually stalls somewhere across the Mid- Atlantic. Coverage of showers and thunderstorms looks highest for Tuesday as an upper level disturbance passes across the central Appalachians. Precipitable water values will remain abnormally high through the period, ranging from 1.7 inches to as high as 2.2 inches for much of the area, which would support the potential for heavy downpours, especially from the slower-moving cells. Warmer than normal temperatures are expected Tuesday and Wednesday. Near normal temperatures are possible for Thursday. && .AVIATION /08Z SATURDAY THROUGH WEDNESDAY/... As of 230 AM EDT Saturday... Areas of fog expected overnight with potential for IFR conditions in the mountains per visibility dropping below 3sm. A period of dense fog is likely in the mountain valleys and along the western slopes of the Appalachians where a layer of low level stratus may form. Any fog/stratus tonight is expected to dissipate by mid morning Saturday with return of widespread VFR Saturday afternoon. Average confidence in the above forecast. AVIATION OUTLOOK... Some lingering showers and sub-VFR possible Saturday evening in the DAN area. Fog possible through the period in the early mornings. The pattern stays unsettled such that daily chances for storms exists. Thinking mainly VFR but sub-VFR when it storms and any late night fog. Confidence is moderate for the extended aviation outlook. && .CLIMATE... As of 300 AM EDT Friday... Record highs and warmest lows temperatures for July 6th. Record high minimum temperatures this morning as well as record highs this afternoon are in jeopardy in some cases. Saturday 07/06/2024 Site MaxT Year MinT Year LoMax Year HiMin Year KBLF 92 2010 44 1972 63 1972 71 1977 KDAN 102 1990 54 2014 70 1972 78 1990 KLYH 98 2010 52 2014 69 1909 74 1900 KROA 100 1999 48 1979 73 1972 74 1977 KRNK 94 2010 42 1972 65 1972 69 1932 && .EQUIPMENT... KFCX radar is running in a degraded state. The radar receiver was damaged heavy rain getting into the radome Friday afternoon. Please use surrounding radars or a radar mosaic until our equipment can be repaired. BLF ASOS...the tipping bucket failed Friday afternoon. Will await the morning Coop report from Bluefield and send a correction to Friday`s climate summary at that time. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...Heat Advisory from 11 AM this morning to 8 PM EDT this evening for VAZ044>047-058-059. NC...Heat Advisory from 11 AM this morning to 8 PM EDT this evening for NCZ006. WV...None. && $$ SYNOPSIS...SH NEAR TERM...SH SHORT TERM...VFJ LONG TERM...VFJ AVIATION...SH CLIMATE...SH EQUIPMENT...PM