Marine Weather and Tide Forecast for Richmond, ME

NEAR TERM /THROUGH TUESDAY/
Early Tuesday morning will feature SFC low pressure well north of the crown of Maine with an upper level trough axis over Upstate NY. The day will start out mostly sunny downwind of the mountains to the coastal plain with continued clouds and scattered snow showers in the mountains.

The upper level low will then move eastward across the forecast area Tuesday afternoon with clouds increasing along with decreasing stability. Modeled Froude numbers are also expected to increase as the afternoon progresses and should aid in multiple snow showers and squalls in the mountains and foothills. Enough moisture and forcing for ascent should be present downwind of the mountains to also allow for a period of snow showers and possible squalls even down to the coastal plain (temps will be above freezing there but very steep low level lapse rates should allow for mostly snow), especially north of Portland. This could actually cause some slippery travel for the afternoon/evening commute and will bear watch.

SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY/
Clearing on increasing westerly winds will be the case Tuesday evening as the short wave trough axis moves east of Maine.
However clouds are expected to once again increase overnight.
Wind gusts during the evening hours may reach 35 MPH or so based on latest forecast soundings but should remain under advisory criteria. Fair and breezy weather is then expected for the balance of Tuesday night.

Another short wave trough is expected to approach Wednesday.
However, moisture will be limited so just a few flurries or snow showers are expected, mainly in the mountains.

LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/
Long Term Update: Just some modifications to Thursday, which will still feature cyclonic flow. Will likely see an embedded shortwave rotate through the afternoon that will extend shower reach from the mountains to the coast...at least through southern ME. NBM PoPs a little overboard over the waters and coast early, but think ocean showers will be realistic once lapse rates increase w/ wave passing in the evening. Steady NW flow with low level moisture makes me confident in steady snow or snow showers in the mountains to the US/CAN border before and after this wave passes. Bumped up QPF a couple hundredths here.
Daytime snow accums likely elevation dependent.

Pattern Overview: Broad troughing overhead mid-week transitions to an upper low that gets blocked over the Gulf of St. Lawrence by an Atlantic ridge in the late week time frame. Several waves rotate around this upper low and through our area, but a lack of forcing at the surface may lead to no more than light showers at times. Models are coming into better agreement on the blocking ridge breaking down over the weekend.

Impacts and Key Messages: * No significant weather impacts expected at this time

Details: Thursday and Friday: Northwest flow continues Thursday as the area remains under the influence of cyclonic flow due to a ridge in the central Atlantic beginning to block up the pattern. Upslope snow showers will continue with GFS Froude numbers suggesting a period of critical flow in the afternoon.
This would allow for a few flakes to make it into the foothills and maybe even down to the coast, but high temperatures in the mid- to upper 40s and a deep warm layer evident on Bufkit soundings, mean these probably melt and end up as sprinkles. Low to mid-40s and a shallower warm layer in the foothills make that the better location to see some flakes. High temperatures in the north look to top out in the mid-to upper 30s. Low temperatures Thursday night end up in the 20s areawide. An upper low forms Friday over the Gulf of St. Lawrence as the the pattern remains blocked. This leaves us in northwesterly flow with shortwaves rotating around the low helping to sustain showers in the mountains, and Froude numbers suggest they will stay there. Continued cold air advection starts a cooling trend with high temperatures in the low to mid-40s south of the mountains, and in the low to mid-30s to the north. Low temperatures bottom out in the low to mid-20s areawide Friday night.

Saturday-Monday: Global models are in reasonably good agreement that the Atlantic ridge begins to break down Saturday allowing the upper low to begin its departure and get the pattern moving again. Upslope snow showers likely start to taper off as the trough finally departs and by Sunday models start to suggest some ridging moving in. How long this ridging lasts is the current sticking point here at the end of the extended forecast period, but there is agreement in some sort of a system early next week so we will be keeping an eye on the trends.

AVIATION /03Z TUESDAY THROUGH SATURDAY/
Short Term...VFR conditions downwind of the mountains for much of today. However, some snow showers ands squalls may affect cigs and vsbys for a time Tuesday afternoon. Westerly winds may gust around 30 kt later Tuesday afternoon and evening.
Widespread MVFR looks likely Wednesday as a weak disturbance moves through the region.

Long Term...Ceiling restrictions of MVFR, possibly IFR, most likely along and NW of the mountains Wed night through Thurs evening. SHSNRA also may lead to vis restrictions at times at HIE and western ME mtns. These showers expand east in the afternoon towards the coast, likely RA. Breezy NW flow Friday and Saturday around 20 kts.



MARINE
Short Term...Seas will build again and gale force gusts are expected starting later this afternoon, going through tonight.

Long Term...Cyclonic flow with an embedded shortwave or two will keep winds W/NW through Saturday. Gale conditions appear unlikely, but can't rule out a short period or few gusts to Gale Fri night/Sat. The offshore flow will see wave heights highest of the period on Thursday, gradually decreasing to 1 to 2 ft for the bays/harbors. Would expect wind wave to be dominant contributor. Instability over the waters late week may promote shower generation just offshore.

GYX WATCHES/WARNINGS/ADVISORIES
ME...None.
NH...None.
MARINE...Gale Warning from 5 PM Tuesday to 7 AM EST Wednesday for ANZ150-152>154.
Small Craft Advisory from 2 AM Tuesday to 10 AM EST Wednesday for ANZ151.