textproduct: Gray - Portland

WHAT HAS CHANGED

For the morning update, just incorporated the latest observational trends into the near term which didn't result in any significant changes. There is a non zero chance an area of light precipitation being driven by a warm front to our west clips the northern portion of the CWA this afternoon, but I am not so sure the dry air in place won't just eat away at it so I left it out for now.

KEY MESSAGES

1. A warm-up is in store through Saturday. A cold front moves through during the day Saturday with the chance for some rain or snow showers in the mountains.

2. Light snow possible Sunday.

3. Brief shot of well below normal temperatures early next week.

DISCUSSION

KEY MESSAGE 1 DESCRIPTION...

A cold front will pass across the region on Saturday with little fanfare, perhaps a few rain or snow showers in the mountains. Southerly winds will increase and become somewhat gusty. The main theme however will be the warm temperatures, with widespread highs in the 40s. A few locations in the far south may reach 50 degrees. Otherwise, up until then, expect dry weather with a gradual warming trend.

KEY MESSAGE 2 DESCRIPTION... After a warm day on Saturday, a s/wv trof will cross on Sunday, likely allowing for a period of light snowfall. QPF looks to be rather low and this combined with marginal surface temperatures into the upper 20s/lower 30s along with the higher sun angle should limit snowfall amounts to an inch or two in most locations.

KEY MESSAGE 3 DESCRIPTION... Canadian high pressure will build over the region on Monday as H8s fall to around -20C. This will limit highs to the teens across the north with 20s south. Wind chill values on Sunday night could approach cold weather advisory criteria in some locations. Monday night will once again be cold with temperatures falling to within a few degrees either side of zero. Temperatures will begin to moderate some on Tuesday as flow becomes southerly. Will need to monitor for some possible precipitation towards Wednesday but forecast confidence is low at this time range.

AVIATION /12Z FRIDAY THROUGH TUESDAY/

Through 12Z Saturday...VFR conditions expected.

Outlook:

Saturday: VFR prevails except perhaps a brief period of MVFR conditions in the mountains on Saturday with a cold frontal passage. Otherwise, southerly winds may gust 20 to 25 knots on Saturday.

Saturday Night: VFR conditions expected.

Sunday: Areas of lower-end MVFR to IFR possible in light snow.

Sunday Night: VFR conditions expected.

Monday: VFR conditions expected.

Monday Night: VFR conditions expected.

Tuesday: VFR conditions expected.

MARINE

Winds and seas remain below SCA thresholds thru tonight. Sat southwesterly winds will begin to increase ahead of an approaching cold front and SCA conditions are likely. Some hi- res guidance suggests a short period of low end gales Saturday morning but this is likely overdone in the WAA regime with the cold SSTs.

NW wind gusts may approach 30-35 kts late Sunday into Sunday night outside of the bays with seas of 3-6 ft. Winds and seas will then lower Monday into Monday night. Another period of increased winds and seas are then possible Tuesday night into Wednesday depending on the track of a low pressure system.

GYX WATCHES/WARNINGS/ADVISORIES

ME...None. NH...None. MARINE...Small Craft Advisory from 9 PM this evening to 10 PM EST Saturday for ANZ150-152-154. Small Craft Advisory from 11 PM this evening to 4 PM EST Saturday for ANZ151-153.