Thursday, 9:30 a.m.
In the video, we look at prospects for the coming weekend and early next week in the Northeast and Great Lakes. Also, we visit the latest version of the forecast for 2 p.m. on Oct. 10. You may recall that we looked at this date on the GFS model early this week and saw what appeared to be a heavy wet snowfall underway in central and northern Pennsylvania. If you don't recall seeing that map, let me say this: we looked at this date (Oct. 10) on the GFS model early this week and saw what appeared to be a heavy wet snowfall underway in central and northern Pennsylvania.
One feature that will affect the weekend weather will be a strengthening trough aloft that heads for the eastern Great Lakes. It will trigger showers, perhaps some thunderstorms and even waterspouts over the Great Lakes as it moves through. This prog map shows where it could be early Sunday morning:
The current surface pattern clearly shows the flow that is bringing ocean-cooled air in from the east. If the high pressure area to the north expands southward as expected by tomorrow, this flow will be weakened and perhaps cut off.
The cold front is embedded in a large area of clouds, showers and thunderstorms covering the middle of the country. It will advance past the Northeast coast by the end of the day Sunday. The frontal zone is shown on this picture from late morning Friday.
When weather systems are relatively weak, small scale variations cause forecast uncertainty because several different weather types (such as showers, sunshine, cloudiness, etc.) can coexist in the same region and change constantly. This map shows such a pattern:
Some of the thunderstorms can become severe, with damaging wind and brief cloudbursts of rain. The greatest chance for locally severe storms should be in the "S" areas highlighted on this map (based on the NWS Storm Prediction Center's guidance).
There is a slight risk for severe thunderstorms later today from north-central Tennessee up across Indiana and Ohio to Michigan and eastern Wisconsin (shown by the "S" area on the map below. Thunderstorms are not predicted for areas near the coast from Delaware to New England.
It is not going to snow any time soon, but in any type of weather the flag is a symbol of freedom. This holiday weekend we celebrate the contributions of those who were there to defend the freedoms we enjoy in these times.