Monday 9:45 AM
A storm crossing the Gulf states dropped heavy rain over a wide area, and the moisture is moving northeastward. However, the upper air trough supporting the rain is shown to weaken slowly on the computer model (I use this term interchangeably with numerical forecasts) maps, and so places in the Northeast should not match the Gulf states in the rainfall amount department. One thing that is apparent is with a persistent flow from the Gulf states to New England, it will be warmer than average for this time of year.
Last week at this time, I showed a GFS forecast map for Oct. 10 that suggested it could snow in central and northern Pennsylvania. I suggested the model would change looks over time and, in fact, the very next run has a warmer look and no snow. On the other hand, a typhoon re-curved over the western Pacific, and this kind of event has often been followed by an upper air trough n the East about 10 days later. The most recent runs of GFS has trended toward this trough in the East scenario, and this suggests next week will be quite a bit cooler than this week (with the first push of cooler air arriving this weekend).
The numerical forecasts (I use this term interchangeably with computer models) for next week will certainly change in various ways before next week arrives, but there are hints that the higher terrain downwind from the Great Lakes could get their first snow showers of the season next week. This map for next Thursday shows a close call setup for this:
Meanwhile, my daily video shows what we can expect this week:
Thunderstorms were widespread across the Midwest yesterday. This map shows the lightning strokes from 8 a.m. ET yesterday. Note how thunderstorms formed along the sea breeze boundary in the Carolinas.
...after all that, the point is that zone will be north of most of the eastern half of the country. It will be very warm to hot south of the jet stream. However, weakening cold fronts can advance south of the jet stream. then return north as the next disturbance in the flow approaches.
Yesterday, the temperature hit 92 at Newark, New Jersey, and 90 in Boston. The following map shows a northerly flow affecting the Northeast today, and so it will be noticeably cooler and less humid.
This map shows lightning strokes from 8 a.m. ET yesterday through 7:54 a.m. ET today. There was quite a bit of it in Utah, Colorado, New Mexico and Arizona. For the whole map, 156,172 lightning strokes were recorded.
Looking at the west-to-east upper air flow over New England well ahead of the storm, it seems like the hurricane should stay out at sea, However, as we look through the series of maps, we see the upper-air flow congealing into a strong eastern trough that helped the storm to come right up the coast instead of heading out to sea.
On this satellite picture, we can see the basically dry weather in the Eastern states. The cold front that will ease the midweek heat in the Northeast is shown by the band of thunderstorms in the Midwest. The thunderstorms may weaken and become more scattered as the front comes into the Northeast.