textproduct: Caribou

SYNOPSIS

High pressure moves well offshore today, followed by a warm front approaching from the south tonight. An occluded front will approach on Wednesday and lift north of the area Wednesday night. Low pressure will track across southern Quebec Thursday and Thursday night, then into the northeastern Canadian Maritimes on Friday. High pressure builds in from the west Friday night and Saturday.

NEAR TERM /THROUGH WEDNESDAY/

645 am update... Quick update to hrly temps and dwpts. Have added in flurries to northern area for an hour or two this morning. NO other chgs needed with this update.

Prev discussion blo... Key Messages -Rain moves in late tonight -May see very brief freezing rain late tonight over central areas with minimal impacts

Upr shortwave rotating thru central Quebec with snow showers just to our north, bringing low-mid deck of clouds over the CWA. Snow showers likely to stay north of the region this morning. 1025mb sfc high will continue to build south of the area with ridge axis shift east and allow return flow to kick with temps rising after 08z.

Cloudy skies expected this morning over the north with high clouds increasing over southern areas. Max temps will top out in the middle 40s over Downeast and around 40 elsewhere.

Upper trof currently dropping into the intermountain west continues digging into the upr Midwest tonight. As it does so it will deepen sfc low that has developed to the lee of the Rockies and will ultimately move into the Great Lakes this evening.

Warm front will lift thru the Ohio Valley this afternoon with precip shield spreading toward New England by 00z this evening. Wave moving along the frontal boundary looks to develop triple point low along the Maine coast around 09z Wednesday. Precip, mainly in the form of rain, moves into Downeast after 06z with a slow progression to the north due to very dry air. Surface temps look to drop below frzg to the north of the Upper Penobscot Valley with the coast and interior Downeast into the middle 30s by the time precip starts. Cannot rule out a very brief chance for snow with any evaporational cooling over central and northern areas but it appears from BUFKIT soundings that blyr temps will be warm enough for all liquid. Given that sfc temps may take a little longer to warm above freezing cannot rule out a very brief period of frzg rain as precip spreads north. Fortunately this looks to be brief with any ice accretion not expected.

Rain looks to finally move into northern areas by the mid morning hours. Temps fcst to rise into the 50s along the coast with upr 30s over the north.

SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/

Deep layered northern stream ridging exits to the east Wednesday night, allowing for a closed low to track from the Great Lakes into southwestern Quebec. The axis of this low lifts to the north Thursday morning, with the center of the low tracking north of the Saint Lawrence River through Thursday night, with its axis moving into Maine late Thursday night.

The result will be rain Wednesday evening, possibly mixing with or changing to snow over the North Woods late Wednesday night. The precipitation then tapers off as rain showers from SW to NE on Thursday (rain/snow showers over the North Woods). Any snow accumulation should be less than an inch across the North Woods, with most portions of the North Woods receiving at most a few tenths of an inch of snow. Could see some isolated to scattered snow showers across the North late Thursday night with the axis of the upper closed low moving in, with little or no accumulation expected.

Lows Wednesday night should be around 15 degrees above normal, highs on Thursday and lows Thursday night around 5 degrees above normal.

LONG TERM /FRIDAY THROUGH MONDAY/

A closed low exits to the northeast Friday, with shortwaves rotating around its base across the region. This coupled with low-mid level cold advection could produce some locally strong snow showers across the North. At this point its uncertain if we will see any snow squalls, but that potential bears watching as the week progresses and that time frame gets within the realm of the convective allowing models towards the middle of the week.

Friday night will feature split flow aloft, with a northern stream shortwave ridge crossing the North and a northern stream shortwave crossing southern portions of the region. For now it seems like the subsidence from the shortwave ridging should win out and other than maybe some lingering showers early, it should be dry.

Locally zonal flow on Saturday gives way to southwest flow aloft by late Saturday night, and with no shortwaves of note progged, it should be dry during this time frame.

Southwest flow aloft continues Sunday and Sunday night. With low level warm advection, should see some light snow across the North and rain or a rain/snow mix elsewhere, with the exception of mainly all snow also being possible across the Upper Penobscot Valley and Northern Washington County. At this time the GFS has a briefer duration and areal coverage of this precipitation than the ECMWF and CMC - given ensemble support leaned towards an ECMWF/CMC blend in this time frame. So could see light to possibly moderate snowfall as a result.

For Monday - there is general consensus we should be under SW flow aloft - however the models differ on whether any shortwaves of note will be embedded in the flow. Given the widespread of solutions from dry to widespread snow or rain across the North and rain elsewhere, limited pops to chance and went with convective vice stratiform wording.

Temperatures should be near normal Friday and Friday night, then below normal Saturday-Sunday potentially moderating to near normal on Monday.

AVIATION /12Z TUESDAY THROUGH SATURDAY/

NEAR TERM: FVE will remain low MVFR thru at least 16z this morning with remainder of terminals VFR. Downeast terminals will drop to MVFR by 05z. IFR after 06z and remain through end of TAF valid time.

HUL will drop to MVFR at 07z and IFR after 09z. Remainder of Aroostook terminals will drop to MVFR after 10z.

All terminals will see IFR conditions in rain on Wednesday. Winds become easterly 5kts in the afternoon.

SHORT TERM: Wednesday night: IFR or lower likely.

Thursday: Becoming VFR from S to N except for possibly at KFVE where MVFR conditions could linger through the day.

Thursday night-Friday night: VFR, except for MVFR or lower possible in any snow showers at northern terminals, with the best chance for any restrictions during the day on Friday. SW winds G15-25KT possible Thursday night-Friday, becoming WNW-NW Friday night.

Saturday: VFR. NW winds G15-30KT possible.

MARINE

NEAR TERM: Southwest winds will approach small craft levels over the outer waters this morning through this evening. Seas increase above 5ft late this afternoon in southeasterly swell. May see seas increase once again by Wednesday morning after a brief 10-12 hour break in small craft levels.

SHORT TERM: SCA conditions are possible on all waters late Wednesday night, with gales then possible on the coastal ocean waters Thursday-Friday night, with SCAs likely on the intra- coastal waters. Will highlight the gale potential in the HWO. Saturday should see SCA conditions throughout, with diminishing winds late in the day.

CAR WATCHES/WARNINGS/ADVISORIES

ME...None. MARINE...Small Craft Advisory until 10 PM EST this evening for ANZ050- 051.