... Disturbance with flurries north this evening. High pressure through early Thu night. Next system approaches Fri. Active pattern persists through the weekend and into next week.
NEAR TERM /UNTIL 8 AM THURSDAY MORNING/... As of 825 PM Wednesday...
Based on winds becoming light and current MOS guidance, lowered temperatures across the board at all sites. Also modified sky cover to better represent current satellite trends.
As of 350 PM Wednesday...
Disturbance moving through Ohio is producing flurries that are making it to the ground. Have updated the forecast to move flurries through northern West Virginia this evening.
As of 1215 PM Wednesday...
Upper level trough continues to shift east of the area this afternoon as a surface high in the Tennessee Valley builds into the region. There has been an increase in mid-level moisture as a weak impulse aloft moves through. This feature has produced a scattered/broken cumulus field that is drifting across OH/IN at this time. Thus, cloud cover will increase this afternoon across parts of the area, particularly northern areas, but not expecting precipitation from this as soundings show plenty of dry air near the surface. Cloud cover will then clear later this evening as the aforementioned surface high moves over the region. This will set the stage for a chilly night and fairly solid radiational cooling conditions with light to calm winds. Lows are expected to dip down into the low/mid 20s throughout the area, but teens are likely in the mountains and even across parts of southeast OH.
With plenty of solar insolation and return flow setting up Thursday as high pressure moves towards the Northeast, temperatures will return to normal values across the area with highs generally in the mid 40s. Cloud cover will then gradually increase across the area late afternoon into the evening as the flow aloft becomes more southwesterly ahead of a mid-level trough,but not expecting any precipitation activity to occur in the near term period.
SHORT TERM /8 AM THURSDAY MORNING THROUGH SATURDAY/... As of 228 PM Wednesday...
Surface high pressure in southern New England will wedge down the eastern slopes of the mountains Thursday night, helping to maintain a shallow layer of sub-freezing air near the surface. Meanwhile, cyclogenesis will take place Thursday night across the northern Gulf Coast as mid-level shortwave energy tracks across the southern US. This will lead to the development of a coastal low that is expected to lift northward along the southeast coast into Friday. Moisture ahead of this coastal system will increase across our area from south to north and override the shallow layer of sub-freezing air near the surface, bringing an opportunity for a period of mainly freezing rain across parts of the area as precipitation initially arrives early Friday morning. Forecast soundings do suggest that the dominant ptype should be freezing rain, but some sleet/snow is also possible on the leading edge of the precip. Areas at greatest risk for freezing rain will be across the eastern sections of the CWA where cold air damming effects will be greatest. However, a brief period of freezing rain could also occur across portions of north central WV as the system initially arrives. Ice accumulation should be pretty light with most of the area looking at 0.05" or less, but still enough to cause travel concerns, particularly on untreated surfaces. Will mention in the HWO for now.
By Friday afternoon, thermal profiles will warm more than enough for any precipitation across the area to be just rain. However, few of the higher ridges in the mountains may stay cold enough to maintain light freezing rain and/or sleet into the afternoon. Any precip activity Saturday afternoon should be pretty light, but with the coastal system tracking southeast of the area Friday night into Saturday and a secondary low approaching from the west, an increase in precipitation coverage across the region is expected. This will result in periods of light to occasionally moderate showers on Saturday with most of the area expected to be rain, but some high elevation snow showers could occur in the mountains during the afternoon.
LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... As of 228 PM Wednesday...
As the aforementioned secondary low merges with the coastal low in the Mid-Atlantic region, this system will then strengthen as it lifts northward and tracks into eastern Canada Saturday night into Sunday. Colder air will move into the region as this occurs and this could allow precipitation across the area to transition from rain to snow Saturday night. The flow will then become more favorable for upslope precipitation by Sunday, with upslope snow showers possible in the mountains and light rain showers across parts of the lowlands.
A brief lull in precipitation chances across the area should then occur by Sunday night as high pressure across the Upper Midwest briefly builds into the area. However, models then indicate that a low pressure system will then develop across the Ark-La-Tex region on Monday, which is expected to lift to the NNE towards our area by Monday night. This system is expected to bring another round of rain and/or snow across the region Monday into Tuesday, but with uncertainty on the track of the system there remains uncertainty in the main ptype at this point. Have maintained a consenus blend of PoPs for now until better model agreement occurs.