|Dew Point:||47.4°F (8.6°C)|
|Wind:||From the ESE at 1.2 MPH|
|Sea Level Pressure:||30.36" (1028.0 mb)|
Heavy RainHigh: 44 Low: 42
Light RainHigh: 52 Low: 37
Chance Light RainHigh: 42 Low: 33
Rain ShowersHigh: 39 Low: 24
Mostly SunnyHigh: 49 Low: 33
Rain and patchy fog. Cloudy, with a high near 44. North northeast wind around 7 mph. Chance of precipitation is 100%. New rainfall amounts between 1 and 2 inches possible.
Rain and patchy fog before 1am, then rain showers and patchy fog. Cloudy. Low around 42, with temperatures rising to around 48 overnight. South southwest wind 2 to 6 mph. Chance of precipitation is 100%. New rainfall amounts between 1 and 2 inches possible.
Rain showers and patchy fog before 7am, then rain and patchy fog. Cloudy. High near 52, with temperatures falling to around 46 in the afternoon. Northwest wind around 7 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.
A chance of rain and patchy fog before 3am. Cloudy, with a low around 37. North wind 2 to 9 mph. Chance of precipitation is 30%. New rainfall amounts less than a tenth of an inch possible.
A chance of rain after 9am. Cloudy, with a high near 42. East northeast wind 2 to 7 mph. Chance of precipitation is 40%.
Rain showers before 4am, then rain between 4am and 5am, then rain showers. Cloudy, with a low around 33. Chance of precipitation is 90%.
Rain showers. Cloudy, with a high near 39. Chance of precipitation is 80%.
A chance of rain showers before 7pm, then a slight chance of rain and snow showers between 7pm and 2am. Mostly cloudy, with a low around 24. Chance of precipitation is 30%.
Mostly sunny, with a high near 49.
... A low pressure system will lift northeast from the Gulf bringing widespread rain to our area through Tuesday. Cold high pressure will build back over the area from the north while another wet frontal system approaches for Wednesday and Thursday, followed by dry weather for the weekend.
NEAR TERM /THROUGH TUESDAY/... As of 230 PM: A deep upper trough continues to dig across the Plains to the Four Corners states, while a ridge amplifies off the East Coast. At the sfc, a 1031 mb high is slowly migrating off the Northeast coast, with a hybrid cold air damming wedge extending southwest thru the Carolinas and GA. Strong deep-layer isentropic lift and upper level divergence is producing a moderate to heavy rain shield across the forecast area attm. This precip is locking in chilly aftn temps, with readings still in the 30s to lower 40s area-wide. Fortunately, thicknesses are supporting all rain, and no freezing temps are being reported in the area.
Tonight, guidance in good agreement on categorical PoPs continuing thru the evening hours, as deep-layer moisture and forcing persist. Strong southwesterly flow atop the wedge will advect increased theta-e and could be enough for some elevated CAPE this evening. The CAMs all show hints of precip becoming more convective-looking in nature, and isolated rain rates may approach flash flood guidance. With that said, the heavy rain/flood threat still looks too low for a Flash Flood Watch, but isolated flooding cannot be ruled out. Precip coverage and intensity should trend downward after midnight, as isentropic lift weakens with a coast low developing and tracking along the Mid-Atlantic coast. There will be enough upglide, however, for spotty light rain and drizzle, and a shallow in-situ wedge should remain in place thru the night. Temps will be nearly steady, and actually rise a few degrees in the high terrain above the CAD air mass.
Tuesday, as an upper trough approaches from the west, a cold front will push into the area, reaching the southern Appalachians by daybreak. The front will be roughly parallel to the flow, and the GFS and NAM show a strong band of frontogenesis developing on the warm side of the frontal zone. This will have enough moisture to produce another round of stratiform rain. The CAMs are in good agreement on generally light rain streaking across the area from daybreak thru early aftn. The lowest levels will see CAA/downglide which should scour out the wedge. Temps will be tricky, as the persisting clouds/precip and CAA should keep temps well below normal. This may be negated by the erosion of the wedge and some downslope warming. With all that said, I did stay on the cooler side of the guidance, highs generally in the lower to mid 50s.
SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... As of 215 pm Monday: An upper low spinning across Texas as the start of the period will wobble into the TN Valley Thu/early Friday, with confluent upper flow expected along the East Coast through much of the period. Cold anticyclone building into the northeast and Mid-Atlantic in the wake of a potent northern stream short wave trough will spill down the Eastern Seaboard throughout Wed/Wed night, which will evolve into strong hybrid cold air damming by early Thursday, as the next round of moderate-to-heavy rain associated with strong isentropic and upslope ascent overspreads the region. The primary concern for this period remains the potential for at least a transient period of freezing rain the climatologically favored areas of the eastern Blue Ridge escarpment, where low level cold advection owing to the classical nature of the CAD as well as upslope flow should provide at least an adequate mechanism for maintenance of cold air. Indeed, there is a strong consensus among statistical and raw model guidance that surface temps will be at or below freezing across much of the northern mtn zones for a good six hours from around 09-15Z Thursday, and this will be during a time in which precip rates should be relatively high. As such, the ice accum forecast has been nudged to to .1-.2 inch from roughly Montreat N/NE to Newland/Banner Elk. This is probably still a bit on the conservative side, as guidance warms temps to above freezing along the escarpment by late Thursday morning, and this may be too soon considering the forecast strength of the CAD.
Otherwise, another day, another cold rain for the rest of the CWA Thursday, with max temps only forecast in the upper 30s-mid 40s across much of the CWA (even temps that "warm" are contingent upon the rain tapering off as quickly as forecast Thu afternoon). Additional qpf of 1.5-2" forecast Wed afternoon through Thu morning may instigate some localized hydro issued depending upon how antecedent conditions evolve over the next 24-48 hours.
We may see a brief period of mountain flurries or light snow showers Thu night as snow levels fall quickly in the wake of a cold front, but the combination of forecast northwest flow/upslope magnitude and moisture depth do not appear adequate to produce accumulating snow showers.
LONG TERM /FRIDAY THROUGH MONDAY/... As of 205 PM EST Monday: The previous deep low pressure that crossed Tennessee late Thursday will be rapidly absorbed in the fast moving west to east 500mb flow over PA early Friday. Medium range models are in reasonably good agreement with dry and cool high pressure starting the weekend as our controlling weather feature. A fast moving cold front originating from northwest Canada will arrive early Sunday. Both the GFS and ECMWF have a thin prefrontal band of moisture which dissipates over the central Appalachians generally from the Bristol area northward. The GFS keeps us dry through Monday night. The old version of the EC had a 500mb shortwave crossing Tennessee Sunday night with wintry precip falling over the mountains and adjacent foothills into Monday morning. The new EC is much more like the GFS and only has a hint of precip for the mountains midday Monday. Temperatures below normal through the period with the warmer day on Saturday with Max Temps only about 3 degrees below normal.