Hello everyone!

A cold front has moved offshore this evening and drier air is working into the area on NW breezes. That dry air will stick around through Sunday and will be accompanied by warm, but not hot, temps. The dry weather will come to an end as tropical moisture streams north Sunday ahead of a cold front due to arrive Monday. Heavy rains are likely to accompany this front before it moves out Tuesday ushering in cool, dry air. This relief sadly looks temporary though as a building ridge looks to bring more heat into the mix by the end of next week.

Today’s forecast worked out fairly well. Skies were mainly clear but some clouds did develop along with a few isolated showers. As expected, an abundance of dry air limited the coverage and intensity of showers. The one issue with the forecast was temps which rose several degrees above the forecast into the upper 80’s in southern NH. This was driven by slight downsloping with WNW winds  as well as sunny skies. Overall, a fairly good forecast with, of course, a minor error or two.

A stretch of quiet weather is likely from now until Sunday evening when a cold front will begin to approach from the west. It will drag a plentiful supply of tropical moisture northward into our area with the cold front separating that tropical moisture from refreshing NW winds which will bring cool and dry air into the region for Tuesday. The biggest question I have regarding the heavy rain threat for this time is how quickly the front can progress east. There is little doubt that cool Canadian air pushing tropical moisture out of the way will result in heavy rains but how long can those heavy rains sit over a particular area? That question can be addressed in the upper part of the atmosphere .

The whole forecast for how much rain we get Monday revolves around the strength of a ridge of high pressure located over the Atlantic ocean. The stronger that high is, the slower the front will move east and the longer the heavy rain will sit over any given location. The trend with recent guidance has been for this ridge to not build to full strength until after the front clears our area. This would indicate a faster front and thus less rain which fits the pattern of disappointment this pattern has brought with regards to drought relief. Also shown in this upper air plot is a digging trough across the Pacific NW which is likely to build a ridge downstream bringing an end to our refreshing weather by late next week.

More details as we get closer.

-Jack

Hello everyone!

Today will feature the passage of a weak cold front which is not much more than a line of shifting winds. The airmass just before the front is slightly warmer and contains just a bit more moisture than the airmass we have now and the one that is behind the front but other than that, you won’t notice a ton of change coming with this front.

We have a very dry airmass in place now with dew points n the mid to upper 50’s for most with some low 60’s across NE areas. Dew points in the low to mid 60’s are located just to our NW across southern Canada. This higher dew point air will filter SE today ahead of the cold front and the added moisture will likely be just enough to touch off an isolated shower or two especially over NE areas. A few showers are already ongoing in those far northern areas as shown on the current observations this morning. The front will move offshore tonight with cool and dry NW breezes for tomorrow. The NW winds behind this front will pale in comparison to those following yesterday’s front seeing as it’s much weaker.

Warm and dry weather is likely to continue through the early part of the weekend. More humidity is likely in advance of an approaching front Sunday into Monday when showers and storms become more likely. Cooler and drier weather is likely to follow that front for the middle part of next week. More on the upcoming week of weather in this evening’s update.

-Jack