Today will feature mild and unsettled weather as plenty of warm moist air flows north out of the Gulf of Mexico, but arrives here without a way to consistently turn into rain. The best mechanism for getting this moisture out of the air is a strong frontal boundary currently extending from the Northern CT Valley up through the Northern Maine mountains. North of this is where the most consistent rain will be falling today.
For areas to the south, there are some showers ongoing at the coast this morning but we’ll need to wait for the remnants of last night’s Mid Atlantic thunderstorms to arrive before we get any steady or heavy rain. That should arrive in Southern NH around 10 AM, with places near Portland holding off until 11 AM-12 PM. That rain will be heavy at times and could contain an embedded rumble of thunder. It will last until the early/mid afternoon, at which point the steady rain will once again be confined to areas north of the front.
Temperatures will be heavily influenced by the aforementioned frontal boundary. North of it, look for highs in the mid 40’s. South of it (away from the immediate coast), high temps will rise into the mid to upper 60’s, with some parts of NH making another run at 70. The midcoast and other coastal areas will once again be cooler, in the low to mid 50’s.