textproduct: Caribou

WHAT HAS CHANGED

Gale warning will expire for the outer waters at 5am.

Updated for 00z aviation discussion.

KEY MESSAGES

1) Temperatures remain much above normal through Tuesday, leading to significant snowmelt and rotting of river and lake ice.

2) Significant precipitation expected Wednesday through Thursday. Low confidence in precipitation type, but significant wintry precipitation is possible especially in the north.

DISCUSSION

KEY MESSAGE 1... Temperatures remain much above normal through Tuesday, leading to significant snowmelt and rotting of river and lake ice.

KEY MESSAGE 1 DESCRIPTION... Temperatures have risen above normal this afternoon, and they only get warmer from here. Highs Sunday will be in the mid 40s to low 50s, Monday upper 40s to mid 50s, and Tuesday mid 40s to around 60. Warmest temperatures each day should be over southern portions of the area, but the whole area will experience warmth and decimation of the snowpack. Many southern locations will lose it all, and over the north, expect the surviving snowpack to just be patchy and mainly limited to more protected areas in the woods. That said, don't expect many flooding issues. We expect rivers and streams to remain in their banks. Some rivers and streams, especially in southern portions of the area, will have some breaking up of ice and some movement, but don't expect a full flushing out of waterways yet and don't expect anything but localized, minor issues. We will definitely be keeping an eye on things though. One positive factor is additional rain through Tuesday will be limited to a quarter inch or less this afternoon through Sunday morning, then dry late Sunday to Tuesday.

KEY MESSAGE 2... Significant precipitation expected Wednesday through Thursday. Low confidence in precipitation type, but significant wintry precipitation is possible especially in the north.

KEY MESSAGE 2 DESCRIPTION... Confidence has increased in a significant precipitation event mainly Wednesday through Thursday. There's about an 80 percent chance of exceeding one half inch of precipitation in the north, and about a 50 percent chance Downeast. For exceeding an inch of precipitation, it's about a 60 percent chance in the north and 20 percent Downeast. These probabilities have been increasing.

Bottom line, we are pretty confident precipitation will fall, but the question is what type will fall. This is where it gets tough. For Downeast, odds favor advisory level or less of mainly sleet or freezing rain, if any does occur. It could also very easily end up all rain for Downeast. For the north, however, there is the threat of highly impactful sleet, freezing rain, and/or snow. There is also a chance (about 30 percent chance) it stays all rain even in far Northern Maine. ECMWF and its ensembles tend to favor the warmer, rainier solution with the main low pressure center passing to our north/west, while GFS/Canadian and its ensembles tend to favor the colder, further south low track with at least a period of impactful wintry precipitation Wednesday to early Thursday. Too early to say what will happen, but did throw some sleet and freezing rain into the forecast Wednesday through Thursday morning for most places because of this distinct possibility.

South winds could also be impactful, especially if the warmer, further north/west low pressure track pans out. High tides are fairly low, so coastal flooding appears unlikely at this point.

Another thing to watch out for is the potential for flooding and river ice breakup if the warmer, rainier solutions pan out for the whole area. But to reiterate, confidence is low in temperatures and precipitation type. To illustrate this lower confidence, for high temperatures on Thursday, the National Blend of Models (NBM) has a 10th percentile of 24F and 90th percentile of 52F in Caribou. This means we can say with 80 percent confidence that the high temperature will fall somewhere between 24F and 52F Thursday in Caribou. That's not a lot of confidence. For Bangor for Thursday, it's 31-58F for the 10th and 90th percentile. Confidence in temperatures increase toward Friday, with cooler air very likely moving in behind the system. Can't rule out more wintry precipitation late Friday into Saturday.

AVIATION /00Z SUNDAY THROUGH THURSDAY/

Tonight...IFR/LIFR with VLIFR at times tonight over Downeast terminals and at FVE. Areas of fog and rain expected through Sunday morning. Conditions improve to MVFR at all but FVE and CAR around 17z Sunday. Southerly winds gusting to 20-25 kts this evening then becoming southwesterly Sunday morning. Southwesterly low level wind shear this evening.

Sunday night...Improving to VFR. SW 5-15kts.

Monday...VFR across all terminals. S wind 10-15 kts with gusts to 25 kts.

Monday night to Tuesday night...Likely remaining VFR. S winds 5-10 kts possibly switching to the NE late Tuesday into Tuesday night.

Wednesday to Thursday...High confidence in an impactful weather system with IFR/LIFR, but low confidence in precipitation type and wind direction depending on the track of the system. Wintry precipitation, including freezing rain and sleet, is a distinct possibility especially at northern terminals. Gusty south winds and LLWS are both possible as well, with the best chance being at southern terminals.

MARINE

A Gale Warning is in effect for much of the waters, with the exception of the intra-coastal waters, this afternoon into Sunday morning. Small craft advisory conditions are then expected through the remainder of Sunday into Sunday night. On the intra-coastal waters, a Small Craft Advisory is in effect this afternoon into Sunday afternoon. A chance of rain this afternoon, then rain tonight. Showers early Sunday. Areas of fog this afternoon into Sunday morning.

Around a 70 percent chance of SW gales late Monday. Corresponding seas building to around 7 ft. Conditions fall below small craft for Tuesday into Tuesday evening. Then for Wednesday through Thursday night, southerly gales are expected (90 percent chance) with seas potentially exceeding 10 ft. Can't rule out storm force winds in this period as well, with the best chance being Thursday with about a 30 percent chance.

CLIMATE

Monday, March 9:

Caribou: Forecast 49 F; Record 47 F set in 1998 Houlton: Forecast 53 F; Record 53 F set in 2012 Millinocket: Forecast 54 F; Record 57 F set in 2016 Bangor: Forecast 56 F; Record 59 F set in 2016

Tuesday, March 10

Caribou: Forecast 46 F; Record 55 F set in 1977 Houlton: Forecast 52 F; Record 58 F set in 1977 Millinocket: Forecast 55 F; Record 54 F set in 2016 Bangor: Forecast 59 F; Record 62 F set in 1977

CAR WATCHES/WARNINGS/ADVISORIES

ME...None. MARINE...Gale Warning until 5 AM EST Sunday for ANZ050-051. Small Craft Advisory until 4 PM EST Sunday for ANZ052.