Apr 17, 2015 8:00 PM
NH1 Weather Insider with Joe Joyce: April 18th, 2015
NH1 Chief Meteorologist- NH1.com
The weekend is finally here and it feels so good. Saturday will start if with tons of sunshine with weak high pressure in place. Temperatures have been mild in the 60's all week, and the mild flow of air remain in place for Saturday. We will have to watch a vigorous piece of upper level energy sliding through New England this afternoon. It is the leading edge of cooler air which will be directed back into New Hampshire tonight. As this cooler air clashes in with the milder air in place, we will have to watch for a few afternoon showers popping up with even the chance for an isolated thunderstorm. This low will cross right over New England Saturday. The best time to expect a few pop up showers would be between the hours of 2 PM-5 PM, other wise the rest of the weekend will be dry. As this low pulls off the coast, breezy NW winds will develop for the late afternoon and evening. Winds could gust to 30 mph. Cooler air with partly cloudy skies for Saturday night in the 30's. High pressure will settle in over us for Sunday with sunshine, lighter winds and cooler temps in the 50's and Lwr 60's.
Big day on Monday in case you did not notice. Marathon Monday will start off cloudy, cool and dry. An upper level ridge on the east coast will make for a decent start to the morning. But as the ridge pulls away, the moist SW flow coming from the Gulf will allow clouds to quickly thicken. A deep upper low will be shifting towards the Great Lakes and help to steer this rain right up into the Northeast along with a warm front. Timing is everything. The way it looks now...the sooner you can finish the Marathon the better off you will be, because conditions will be going down hill in the afternoon.
Rain showers will develop Moday afternoon. Cool SE winds will become breezy. The inclement conditions will help keep temperatures near 50. Rain will become heavier Monday night through early Tuesday where heavier downpours will be possible. By Tuesday morning, another wave of low pressure will be developing on a cold front which will track into Southern New England. This will likely aid in helping to keep the rain going in the morning, before finally tapering off to showers. Over 1" of rain is expected with this disturbance which could lead to some minor street flooding, as well as rises on area rivers and streams.
The Upper low over the Great Lakes will be shifting east for most of next week. This will help to suppress warmth south of us, keeping temperatures seasonally cool, along with providing periodic instability showers almost everday as pieces of lift in the upper level flow will enable these periodic showers from time time. Temperatures will be cool enough in the mountains for even a few snow showers sometime next Wednesday or Thursday. The Mild days are coming to an end for now. Cooler times ahead as we end out the month of April. Have a great weekend!