|21Z (3 PM) Saturday NAM 250 mb Heights and Wind (kt) over 50 knots. Notice the coupled jet streaks over the central Appalachians and the New England Atlantic coast.|
At the surface, the high pressure will move east and quickly break down as a surface low sweeps across the lower Great Lakes, with an expected cold frontal passage around 6 AM Sunday. On Saturday, expect a slight warming trend ahead of the front. This is looking to be the main focus for precipitation for the forecast period, supported by the strongest 700 mb vertical velocity returns. Even so, moisture advection will be very slight and brief before the frontal passage. The significant nose of moisture is staying just south of south-central Kentucky shown below.
|00Z (6 PM Saturdy) Sunday GFS 850 mb Mixing Ratio and Wind (vector). Notice the broad, but weak advection of moisture with the major nose only extending into northern Alabama.|
The freezing line will be bisecting and to the south of the area, so any precipitation that falls could be mixed or in the form of snow. With the lack of moisture, I will keep the forecast dry. After the cold frontal passage, ridging aloft will take over and a surface high pressure will settle into the area giving way to a warming trend into the next week.
Forecast at a Glance:
Today: High: 41 Low: 21 Precip: 0% Wind: NW to N at 4-7 mph
Friday: High: 39 Low: 22 Precip: 0% Wind: NW to W at 6-8 mph
Saturday: High: 45 Low: 28 Precip: 20% chance of mixed Wind: SW at 5-10 mph
Sunday: High: 38 Low: 23 Precip: 30% chance of mixed/snow Wind: SW at 5-10 mph switching to NW at 10-13 mph then to 4-7 mph late.
Forecaster: Austin Boys