... Strong low pressure system drives a warm front through, followed by a cold front today. Strong winds this afternoon. Dry Sunday. Upper level disturbances Monday and Tuesday.
NEAR TERM /THROUGH TONIGHT/... As of 140 AM Saturday...
Areas of fog have developed as a break in precipitation continues across much of the area. Rain and storms will spread back into the area early this morning as a passing low pushes a cold front towards the area. Have adjusted PoPs to better reflect current trends this morning.
As of 644 PM Friday...
Adjusted down hourly temperatures to better match latest surface observation trends. A north to south temperatures gradient exists, basically, in the 40s north of a line from HTS, northeast through CKB, while in the 60s south of such line. With plenty of cloudiness and the fact that the frontal boundary is quasi- stationary, temperatures will slowly go down through midnight, and then gradually increase under increasing southwest flow ahead of the approaching cold front during the predawn hours Saturday.
Latest high resolution models are in timing agreement, bringing convection, with strong gusty winds arriving at our Tri-state (KY/OH/WV) area by 08-09Z Saturday morning.
As of 230 PM Friday...
* Ongoing showers will contribute to flooding concerns in the midst of a lifting frontal boundary tonight followed by a cold frontal passage on Saturday. * Strong winds mix down to the surface in the wake of a cold front on Saturday, with gusts capable of reaching 45-50 mph in the afternoon.
A stalled frontal boundary cuts the forecast area in half today. Across the north, stable rain cruises through southeast Ohio into northern West Virginia with temperatures residing in the 40s/50s. Precipitation rates have been light in intensity, but have been ongoing since last night, promoting localized areas of flooding in southeast Ohio where a rise in creeks and streams have been observed.
Areas located south of the frontal boundary paint a different tale. Warm air advection along southerly flow has allowed current temperatures to rise into the upper 60s/low 70s and partial clearing skies. Looking upstream in Kentucky, a line of heavy showers continue to encroach the southern WV coalfields with the potential for thunderstorms later on in the afternoon. SPC Mesoscale Analysis depicts the best dynamics set up for convection in southwest VA and southeast WV, lining up well with where latest satellite imagery shows clear to partly clear skies and the warmest temperatures have been observed. This could lead to one or two rounds of isolated storms from now into this evening, unless the atmosphere becomes overworked with this first line of stronger radar returns passing through the region.
Heading into the late evening hours, a low pressure system ejecting out of the ArkLaTex area will set its sights on the Great Lakes region. This feature will cause a northward shift in the stalled frontal boundary in our forecast area all the way down into the Tennessee and Mississippi Valleys as a warm front. The likelihood of showers retreats north and westward overnight due to this northward shift, allowing a dry slot to ensue in the eastern half of the RLX forecast area. This becomes short- lived heading into Saturday morning as the surface low drives a cold front into the Ohio Valley. Showers and embedded thunderstorms will precede the frontal passage in the predawn hours Saturday morning. This will bring the last slew of heavier rainfall amounts, and concluding the concerns of flooding potential Saturday morning. The Flood Watch will then come to an end.
Looking at Saturday afternoon as the cold front makes eastward progress through the area, daytime heating coupled with moisture residing ahead of the front may produce isolated convection in northeast West Virginia. Any activity that is able to develop within this environment will be low-topped, and diurnally driven.
To top things off, a strengthening low level jet takes aim at the Central Appalachians on Saturday and yields strong wind gusts for much of the area. Forecast soundings depict 40-50kts arriving early Saturday morning in a capped environment out ahead of the front, alleviating winds initially at the surface. After daybreak, however, winds on the upwards of 45-50 mph could be maximized on account of both the frontal passage and daytime mixing. In coordination with nearby offices, a Wind Advisory will go into effect mid-morning and continue through most of the day Saturday. The surface low departs into Canada late Saturday, with gradient winds relaxing from west to east. Surface winds will then begin falling below advisory criteria at the conclusion of the near term period, but holds for a few more hours along the higher terrain.
SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/... As of 210 AM Saturday...
Surface high pressure will allow for dry weather on Sunday. An upper level disturbance will then provide a chance of showers on Monday. A stronger upper level disturbance and associated surface low will then provide even better chances of showers on Tuesday. Even so, both system on Monday and Tuesday should have precipitation amounts that are on the lighter side, so no flood threat.
Some colder air behind the system Tuesday night could provide some light upslope snow or flurries, but nothing significant.
LONG TERM /WEDNESDAY THROUGH FRIDAY/... As of 210 AM Saturday...
A high pressure system will build over the region and provide dry weather for Wednesday. This will be rather short lived however, as another system will provide for additional precipitation for late Thursday into the weekend. Models are in disagreement in the details of this system however, so confidence in the timing of rainfall is low.