textproduct: Caribou

WHAT HAS CHANGED

- No significant changes.

KEY MESSAGES

1) Areas of frost possible tonight. Precautions should be taken to protect sensitive vegetation.

2) Much warmer Wednesday through Friday, with two dry days in a row areawide Wednesday and Thursday.

DISCUSSION

KEY MESSAGE 1... Areas of frost are possible tonight. Precautions should be taken to protect sensitive vegetation.

KEY MESSAGE 1 DESCRIPTION... Confidence in frost across portions of the north is running around 60-70% percent. The questions are do the winds go calm and how much cloud cover is there? Models and satellite point towards some mid clouds pushing down from the NE tonight in response to the axis of the northern stream trough pushing south through the region. The uncertainty lies in will it be clear for long enough in between these clouds and the exiting clouds from the northern stream shortwave exiting to the south to allow for frost formation. If so, will the winds be light enough to allow for frost as well. I believe the answer to the latter is yes. As for the former, I am only 60-70% confidence in that. The answer to the latter is key in determining if we radiate sufficiently to be cool enough for frost. That is the hang up, right now have forecast temperatures that are generally marginal for frost formation for later tonight. Since the confidence in widespread frost occurring is below the required 80% confidence to issue headlines, will let the evening shift evaluate if a Frost Advisory is need across portions of the North for late tonight or not.

KEY MESSAGE 2... Much warmer Wednesday through Friday, with two dry days in a row areawide Wednesday and Thursday.

KEY MESSAGE 2 DESCRIPTION... On Wednesday, ridging builds in from the west as a high pressure system settles over the Great Lakes region. Warmer air mass with warmer temperatures expected for the end of the week. Daytime high temperatures in the low-to-mid 70s on Wednesday, upper-70s to low-80s on Thursday, and mid-70s to low-80s on Friday. Overnight lows generally in the 50s. Not anticipating precipitation Wednesday or Thursday. Cold front begins to approach on Friday, bringing a chance for some rain showers in the afternoon.

AVIATION /18Z SUNDAY THROUGH FRIDAY/

High confidence in VFR through the TAF period, with the possible exception of a very low chance (10-15%) of a brief period of MVFR with any passing shower at KBGR this afternoon.

Winds are out of the east at northern terminals at 7-10KT with sea breezes at southern terminals and wind speeds around 10KT. All terminals should see winds go light and variable by early to mid evening. Most terminals should see winds increase to 6-10KT out of the NE by late Monday morning.

Monday afternoon/night: High confidence in VFR, except for a very low chance of a brief period of MVFR in any showers in the afternoon.

Tuesday - Tuesday night: VFR, with a very low chance of brief MVFR conditions due to rain showers at KHUL/KBGR/KBHB in the afternoon to evening period. NW winds that could gust 15-20 kts Tuesday afternoon. Winds relax and go variable overnight.

Wednesday - Thursday night: VFR. Winds shift S by Wednesday evening, and then SW by Thursday.

Friday: VFR, with a very low chance of brief MVFR conditions at KFVE/KCAR/KPQI/KHUL in the afternoon to evening period. WSW winds around 5-10 kts.

MARINE

A relaxed pressure gradient over the waters through Monday night will limit winds to 10 kt or less and seas to 3 ft or less.

Winds and seas generally stay below Small Craft criteria next week. Brief period of rain showers possible Tuesday afternoon into evening. Winds from the SW Tuesday, shifting clockwise Wednesday.

CAR WATCHES/WARNINGS/ADVISORIES

ME...None. MARINE...None.