Special update this evening to bring you my latest thoughts on this weekend’s storm system. Right now, things are looking pretty similar to how they were this morning. 12z models did continue the westward trend but it looks like we still miss out on the brunt of the storm.
Right now, rain is already moving into parts of CT and RI for the trick-or-treaters. This is a little ahead of schedule and could have some
This storm will be divided into two parts. Part one arrives Saturday morning and lasts through Saturday evening. This will be primarily rain for our area and will involve NE winds of around 20mph gusting to 30mph. Winds during this time will be out of the NE. This is when the bulk of the QPF (the amount of liquid that will fall from the sky) will fall. After this low passes by, winds turn to the NW, precip slows and phase two begins.
Phase two involves the second low developing and passing offshore. Column saturation loss looks likely Saturday evening which should lead to precip becoming more drizzly in nature. Cold air will begin to flood southward at this point and begin to transition precip to snow. This is where the biggest forecast challenge lies. If the second low tracks more to the West, we get more QPF out of it but the snow line gets pushed farther west. If the storm passes farther east, there is less in the way of QPF but the snow line would make it farther south. This second low could even miss us altogether and bring flakes exclusively to the Midcoast.
Right now, it looks like the most likely scenario is that the first low delivers rain to most and snow to the high elevations while the second low passes farther offshore. I think most in Maine and New Hampshire see snow this evening with the most snow falling in Downeast Maine (over a foot is expected by NWS Caribou) tapering down to a few flakes flying over Southern and Coastal areas.
Snow map for Saturday and Sunday. Click to enlarge.
Winds will be a big issue as well as the storm rapidly intensifies. Expect the highest winds along the coast with gusts surpassing 50 mph at times especially Saturday night.
Peak wind gusts Saturday and Sunday. Click to enlarge.
I’ll be busy most of the day tomorrow but will likely have a mid-storm update tomorrow evening.
Apologies for the late update, there was an unusual amount of data that had to be looked at this morning to come up with the forecast. Today will feature increasing clouds ahead of the storm. Weak warm air advection may bring a sprinkle or flurry to the mountains later in the day but otherwise, no interruptions for trick-or-treaters. Temps this evening will be falling through the 40’s.
As for tomorrow, models are slowly coming into better agreement in terms of how the storm will play out. The GFS is the most excited about the storm idea with the JMA not far behind. The Euro is still pretty excited but not nearly as much as the GFS. The NAM remains completely uninterested.
Here’s how I think it will play out. Top-down saturation of the column will allow for some light snow after midnight for the mountains. Rain moves in Saturday a little before noon at the coast and spreads NW throughout the early afternoon in association with the first low. Rain becomes more showery in nature for a brief time Saturday evening before picking up again Saturday night. Once night falls, cold air will start to flood south as the storm intensifies so a gradual change to snow can be expected starting in the mountains and eventually making it all the way to the coast by Sunday morning. All precip moves out Sunday midmorning.
Here’s my thinking on accumulations. Even heftier totals will probably fall in Downeast Maine.
Winds will be another issue as they would be anytime a storm rapidly deepens off the coast. Wind gusts will be strongest across coastal areas with gusts reaching 50mph at times. Sustained winds will be much lower however likely not making it out of the 30mph range. Power outages could be a big problem especially if snow happens to be on the branches when the wind is strongest (Saturday night).
Much cooler air moves in for Sunday with highs even at the coast not making it to 40.
Today will feature mostly sunny skies across the region with the mountains seeing a few more clouds. Temps today will rise into the 40’s in the mountains and 50’s elsewhere. All and all, it will be a pretty quiet day.
As for our weekend storm threat, it’s looking more and more likely that we see just a glancing blow as the storm moves OTS. All 0z models, operational and ensemble means take the storm east of the 40N 70W benchmark which is the ideal location for a New England heavy precip event. Snow will still fall in the favored upslope areas as well as Midcoast Maine. Cape Cod and SE MA are at risk for some rain showers as well.
Today will feature mostly cloudy skies (although some sunny breaks are possible this morning) and the chance for some showers. The best chance for showers arrives in the Mountains this morning then slowly transitions S and W eventually reaching the coast by evening. These showers are in association with a cold front so today will be very mild compared to past days with highs in the 60’s for all.
WEEKEND STORM UPDATE
No significant changes happened with the models overnight, the GFS trended slightly farther west towards a more Euro-like solution although it still has rain/snow for eastern areas only (as opposed to the Euro which gives everyone rain/snow). Right now, I am leaning more towards a Euro like solution because of the Euro’s track record, support from all the teleconnections, and a favorable upper air pattern with a trough in the West (which supports another trough in the east) and ridging in the Atlantic. However, despite these factors, there is still far too much disagreement among the models to firm up any forecast. If for some reason, models are in more agreement with the daytime run, I will have another post tonight with more detail. If not, the next update will be tomorrow morning.
Today will feature calm conditions as we sit under a sprawling high pressure system. Expect temps to be a little warmer with highs in the 60’s for southern areas. Maine and Northern New Hampshire still get to enjoy 50’s for the time being. Some showers are moving out of the mountains this morning and the theme of widely scattered showers should continue throughout the day. Nothing widespread or heavy is expected.
Enjoy the warm temps while they last because they will be gone in a flash. Tomorrow afternoon features the passage of a strong cold front. Expect gusty NW winds behind the front. Thursday appears to be a nice day with temps a little cooler than normal. Friday continues the cool streak but with significantly more clouds out ahead of our next system.
That next system is the one that looks to impact the region Saturday possibly into Sunday. The models are about as split as Congress is right now with the Euro going big and putting a large, developing low in the Gulf of Maine. The GFS has more of a norlun trough setup as it skirts the main low farther east. For now, I would say that some precip is likely. As for how much/when/what type, we’re far from figuring that out.
Today will feature a classic post-frontal day with gusty NW winds and upslope clouds/showers. In some of the higher elevations, these showers could fall as snow. Highs today will range from the 40’s in the mountains to 60’s in CT. Downsloping should keep the coast mainly clear regarding cloud cover today.
Regarding the rest of the week, expect another calm and cool day Tuesday, more clouds Wednesday, gusty winds and more upsloping Thursday, and more clouds and possibly some rain Friday. The upcoming weekend is still very much under debate as far as potential scenarios go. RIght now, I am leaning towards a rain event changing to snow Saturday. Strong winds are also possible with this event. I will do a full breakdown in the coming days.
Today will feature a few scattered showers this morning but other than that, the rain is pretty much done. The final day of our four day nor’easter saga will be front-loaded meaning most of the action will be in the morning hours. We might even see the sun late this afternoon! If not, don’t worry, everyone gets to soak up the sunlight tomorrow.