Stonington ME to Port Clyde ME Marine Forecast
|Tonight...Se Winds 25 To 30 Kt, Becoming Sw After Midnight. Gusts Up To 45 Kt. Seas 9 To 12 Ft. Rain With A Chance Of Tstms This Evening, Then Rain Likely After Midnight. Vsby 1 To 3 Nm.|
|Fri...W Winds 20 To 30 Kt With Gusts Up To 40 Kt. Seas 7 To 10 Ft, Subsiding To 5 To 8 Ft In The Afternoon. A Chance Of Rain. Vsby 1 To 3 Nm In The Morning.|
|Fri Night...Nw Winds 20 To 25 Kt, Becoming W 15 To 20 Kt After Midnight. Seas 4 To 6 Ft.|
|Sat...W Winds 15 To 20 Kt With Gusts Up To 25 Kt. Seas 3 To 5 Ft.|
|Sat Night...W Winds 10 To 15 Kt With Gusts Up To 25 Kt. Seas 2 To 4 Ft.|
|Sun...Sw Winds 5 To 10 Kt, Increasing To 10 To 15 Kt With Gusts Up To 20 Kt In The Afternoon. Seas 2 To 4 Ft.|
|Sun Night...S Winds 15 To 20 Kt With Gusts Up To 25 Kt. Seas 4 To 6 Ft.|
|Mon...S Winds 20 To 30 Kt With Gusts Up To 40 Kt. Seas 9 To 12 Ft. Rain. Vsby 1 To 3 Nm.|
|Mon Night...Sw Winds 15 To 25 Kt With Gusts Up To 35 Kt. Seas 11 To 16 Ft. Rain. Vsby 1 To 3 Nm.|
|Tue...W Winds Around 15 Kt With Gusts Up To 25 Kt. Seas 7 To 10 Ft.|
|Tue Night...W Winds 15 To 20 Kt With Gusts Up To 25 Kt. Seas 6 To 9 Ft. Winds And Seas Higher In And Near Tstms.|
Area Forecast Discussion|
National Weather Service Gray ME
736pm EDT Thu April 9 2020
Moderate to heavy rain, snow, and some sleet are expected through this evening as a coastal storm deepens and moves along the coast. Winds will also be gusty this evening. The storm will move quickly out of the area later tonight, leaving behind cooler temperatures and snow squalls in the mountains for Friday. Winds will be gusty once again on the backside of the system. High pressure returns on Saturday with temperatures running above normal this weekend. The next system arrives Monday with heavy rainfall possible.
Near Term - Tonight
730PM Have updated the forecast with latest thinking on snow totals and timing, although not a lot of change was made. Upped the totals a bit near Augusta where the most prolonged period of onshore moisture surge continues through the evening. We can see the low wrapping up even on radar imagery and expect a continued area of heavy snow falling within the wrap around area mainly across western Maine this evening. With the heavy wet nature of the snow and temperatures mostly above freezing, think that a significant amount of compaction will occur which will lower storm total snowfall amounts from what might otherwise be reported. But it seems like a very heavy, thick 10 or 12 inches is likely just inland of the Midcoast with higher totals further north. Current headlines fit the latest forecast thinking well, although we will likely be able to drop parts of the winter headlines early. As for wind, there is still a chance of gusty west winds this evening in southern New Hampshire, though it seems this should be timed for later in the evening closer to midnight when the best cold advection begins down there. Will maintain the Wind Advisory, though confidence in criteria being met has lowered.
515PM We are upgrading the Midcoast to a Winter Storm Warning as mesonet obs show temperatures right around 33 or 34 degrees with snow falling in most of these zones. Immediate coastal locations like Rockland airport are still 39 and rain, but even here this is expected to change. Similar impacts expected here as mentioned in prior update further southwest.
430PM We have decided to expand the Winter Storm Warning a bit further south into central Cumberland County and advisory for interior York and coastal Cumberland. This is based on observations showing very heavy wet snow falling and expanding southward. Although the back of the precipitation is approaching through New Hampshire at this time, we expect redevelopment as the low strengthens in the Gulf of Maine this evening. The heavy wet nature of the snow will make it even more slippery than normal and could weigh down tree branches enough to cause power outages.
ORIGINAL A coastal storm continues to develop this afternoon over eastern Massachusetts. Latest CAM models show the system hugging the coast through this evening, pivoting and continuing to deepen as it rotates across the coast. We are already seeing a mix of p-types across the area, including rain, snow, sleet, and graupel with the stronger convective elements. Temperatures aloft are isothermal, so as melting and other processes continue many places will switch back and forth between liquid and frozen precipitation. As far as convection is concerned, most of the instability remains to the south. However, rapidly increasing lapse rates have created conditions favorable for lightning over the area. This chance for thunderstorms will remain in the forecast through this evening.
Expecting snowfall rates to be in the 2-3" range at the height of the event later tonight as frontogenesis is maximized in the dendritic growth zone, causing heavy, wet snow to pile up quickly. There will be a tight snowfall amount gradient between the advisory/warning level in place, so some areas may get very little as they mix in with rain along the coast, while on the northern side of a county higher amounts may be realized.
Snow will eventually become the dominant precipitation type tonight as colder air is pulled south on the backside of the low. Where it will be mostly rain, liquid precipitation rates will also be high, at least an inch an hour. This may cause some poor drainage flooding at times. A dry slow should arrive in the early morning hours and erode precipitation across southern NH and SW ME.
Strong winds throughout the column will mix down to the surface in any heavy precipitation. In particular, along the Mid Coast where the onshore component will be strongest, a wind advisory remains in place for gusts to 50 mph. In addition, similar wind speeds are likely for southern NH as the storm tucks in along the MA/NH coastlines and downward momentum transfer brings higher winds just off the surface to the ground.
Temperatures will not vary much overnight but should cool into the upper 20s to lower 30s.
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/... The system pulls away and lingers near Bangor, ME tomorrow morning before pushing into the Canadian maritimes. Strong NNW winds will continue to usher in colder air, and MOS guidance is becoming more bullish with gusty winds over portions of the area. May need a wind advisory tomorrow during this time, but with the current winds advisories and a lull between the two periods of higher winds, will deal with that once the system is more or less past.
The upper low remains overhead tomorrow, and will see widespread rain and snow showers. These will be much lighter than today except for the higher terrain where RH and winds in the 950-850mb layer will support snow squalls with heavy snow and low visibilities at times. This will primarily occur between around noon through 6 pm and affect areas along the CT River Valley, north of and including the White Mountain National Forest, and northeast towards Jackman. Some of these stronger squalls may make it into the foothills but will lose steam as terrain support decreases.
Highs will reach the upper 30s to upper 40s in the area.
Long Term - Saturday Through Thursday
An active, troughy weather pattern continues through the extended forecast period. Long-range model suites agree on the upper air pattern during this time, namely with the development of deep, anomalous troughing over the Plains by the start of the next week. While this brings down a strong shot of cold air into the Plains, it leaves us on the warm advective side of things heading into the next work week. A preceding shortwave will deliver a shot of moderate to heavy rain early in the week with a dry trend to follow as troughing shifts east (although not entirely dry).
On Saturday, breezy northwest flow continues as the trough responsible for the messy weather today gradually lifts through the Canadian Maritimes. Upslope snow showers continue near the international border through the day, then high pressure nosing in from the southwest gradually clears the area of showers and most clouds. Expect a fairly nice Sunday with breezy southwest winds, mostly sunny skies, and temperatures topping out in the 50s to near 60 over the lower elevations as high pressure passes to the south.
Sunday night, aforementioned deep troughing develops and digs southward through the Plains, phasing with the southern stream. A southern stream shortwave kicks out ahead of the long wave and rides NEward, leading to strong cyclogenesis over the mid-Mississippi Valley into the Great Lakes Region. Low pressure eventually tracks NEward into northern Quebec by the end of Monday, during which time broad warm frontal forcing overtakes the northeast CONUS. As we've seen in numerous storms this cold season...including today, as an extreme example...re-development of low pressure is probable as the front reaches the coast, although it seems to be weaker than in other systems being as detached from parent forcing as it is. Precipitation may begin in the southwestern zones as early as Sunday night; model ensembles focus most precipitation during the afternoon and evening on Monday. Little change in the Quantitative Precipitation Forecast forecast with a general 0.75-1.5" focusing on the coastal plain extending north into the mountains, falling as rain.
Stratiform rain moves out to the northeast Monday night with a drying trend to follow. The shortwave becomes ingested in the broader trough which continues to spin overhead into the middle of the week with enhancements as cold fronts drop down from it. This keeps shower chances at least in the mountains with a return to near- normal temperatures.
Coastal storm will rapidly develop in the Gulf of ME through this evening, and high end gale warnings remain in effect thru Friday. Will have to watch the Cold Air Advection behind the deepening low early Friday...where gusts may approach storm force well outside the bays.
Long Term...Seas back down below 5 ft by Saturday morning, but offshore flow may gust near 25 kts over the waters Saturday afternoon. High pressure crosses to the south Sunday. The next area of low pressure crosses the region on Monday with increasing onshore flow, possibly to Gale Force, and increasing wave action.
A period of heavy rain and some embedded thunder is likely along the Maine coast this evening...transitioning to snow over for areas just inland in some cases. Given snow in the mountains and foothills and a rain/snow mix just south...significant river flooding is not expected. May have some short-fused issues at the coast especially with water levels rising towards the 1 AM Friday high tide which may prevent efficient drainage. This event may also prime some locations for water problems with another opportunity for heavy rainfall Monday.
Tides / Coastal Flooding
Astronomical tides are near peak for the month and already near flood stage without wind and wave forcing. With a strong coastal storm continuing through this evening and winds increasing, expect areas of minor flooding and additional splashover and beach erosion. Storm surge values should max out around 2 ft...but crucially the timing will miss high tide by several hours. Coastal flood advisory remains in effect for the next tide cycles.
The last GYX upper air observation was March 25 at 12Z. Unfortunately, a disruption in gas supply has temporarily halted observations from GYX. At this time it is unknown when observations will resume.
The Sugarloaf NWR transmitter has returned to service.
NOAA Gray/Portland ME Office - Watches - Warnings - Advisories
ME...Winter Storm Warning until 8am EDT Friday for MEZ012>014- 019>022-025>028-033. Winter Storm Warning until 2pm EDT Friday for MEZ007>009. Winter Weather Advisory until 8am EDT Friday for MEZ018-024. Coastal Flood Advisory until 3am EDT Friday for MEZ023>028. Wind Advisory until 11pm EDT this evening for MEZ027-028. NH...Winter Storm Warning until 2pm EDT Friday for NHZ001>004. Wind Advisory until midnight EDT tonight for NHZ007-008- 011>015. Coastal Flood Advisory until 3am EDT Friday for NHZ014.
Gale Warning until 11am EDT Friday for ANZ150>154.