May 25, 2016 1:10 AM
NH1 Weather Insider with Joe Joyce: May 25, 2016
NH1 Chief Meteorologist
National Weather Service Text Product Display
An upper level trough will finally pull away from the area today leaving a more progressive and zonal upper air pattern in place. Warmer west winds will push temperatures back into the mid-upper 80's during the afternoon. Some in the Merrimack valley may even reach near 90 under mostly sunny skies. A weak frontal boundary tries to nudge south out of Canada and into the mountains of New Hampshire and western Maine later this afternoon. This feature may generate enough instability to get a few scattered showers or thunderstorms going...but they should be relatively weak and unorganized, and mostly reserved for the north country.
Warm weather continues Thursday as high pressure builds in further at the surface and aloft. Temperatures should warm quickly in a relatively dry airmass with some clouds remaining over the higher terrain and mostly sunny skies across the coastal plain. Highs will again hover in the mid-upper 80's inland with 70's at the coast. A warm front approaches from the SW during the afternoon-evening hours...but it will take a while for the atmospheric column to saturate so not expecting anything but sprinkles and scattered showers showers will spread in along this stalled front Thursday night and Friday morning.
By the early morning hours Friday, we should see more coverage over NH and western Maine. The warm front will lift across northern sections providing a focus for showers and thunderstorms along the boundary with decent instability for areas far enough away from the onshore flow. Humidity will be increasing during the Friday to Saturday time frame, so any showers which do form could come with some locally heavy down pours. Of course on Friday, it will depend where this front sets up across the state. The cooler side of the front will be in the 70's, the warmer will be in the 80's.
Saturday will be warm again well into the 80's, but a cold front will be pushing back inot the region. The cold front will trigger more widespread convection with another chance at scattered showers and thunderstorms Saturday afternoon. Behind this cold front, The cool air regime continues with more air moving in from the Canadian maritimes through and a serious push of cooler marine air arriving Sunday and Monday. The back door front will push back to New York state. Western New England will remain warm, but a cooler marine airmass will take hold across eastern new England for the second half of the Memorial Day weekend. High pressure will be parked off the coast supplying enough dry low level air to prevent many showers Sunday or Monday, but we will have to watch for low clouds backing in off the water which could create cloudy skies and cooler temperatures in the 60's and 70's, even 50's will be likely at the coast. There is plenty to watch and be mindful of in the Weekend forecast. Slight changes will mean big differences to the forecast and the overall feel.