Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Caribou ME
805 PM EDT Tuesday may 5 2015
a cold front will slide across the region tonight from Canada.
High pressure will build down from Canada on Wednesday and remain
across the region through Thursday. A warm front will lift across
the region on Friday.
Near term /through Wednesday/...
8 PM update...
secondary cold front is spreading virga showers across The Crown of Maine
this evening. Dewpoint depressions range from 20-25 degrees under
extremely dry airmass but will continue chance showers this evening across
far north as there were a few drops on windows earlier. Only other
change was to tweak hrly T/dew point values and winds. Have allowed red flag
warning to expire on time.
Previous discussion below...
The main focus as has been the last few days will once again be
A second cold front will drop southeast from Canada this evening west/some
showers. The NAM and GFS soundings show the best support for
showers across northern Maine north of the Millinocket-Houlton
region. Lapse rates in the 850-500mb layer prognosticated to hit 7.0 c/km
through about 8 PM in the aforementioned area. Sb cape to be <
100 joules west/lifted indices above 0. 0-6km shear of 40 kts. Decided to add
some wind gust potential to 35 miles per hour west/the heavier showers. Showers
will fall apart as the front drop southeast tonight and forcing weakens.
Skies are expected to clear after midnight and winds to drop off
below 10 miles per hour especially from Houlton on south. Airmass behind this
front is cooler and drier. Therefore, overnight temperatures will
drop back to at or just below normal readings by early Wednesday
Decent jet maximum of 50 kts from 850 to 700 mbs showing up on the
12z upper air is set to move across the region on Wednesday. Plenty of
sunshine and low level lapse rates(0-3 km) of 8.0 c/km and the jet maximum
will be enough to get mixing potential especially Wednesday
afternoon. Momentum Transfer off the BUFKIT profiles show gust
potential of 30+ miles per hour across much of the County Warning Area. Daytime temperaturesarea
forecast to be near at or above normal. All this leading to very high fire
danger once again. More on this in the fire weather section below.
Short term /Wednesday night through Friday/...
Thursday will bring weak high pressure across the area. A frontal
boundary extending from northwest to southeast across the state will
Divide dry and somewhat cooler air to the north from warmer air to
the south. This will bring partial sunshine to central areas with a
mostly sunny sky over the north and south on Thursday. Thursday
night will be dry and seasonably cool. Low pressure tracking through
central Canada on Friday will pull the frontal boundary north as a
warm front. Humidity will increase a bit in southwestern areas. The
north will be mostly cloudy as the warmer and slightly more humid
air pushes north and some spotty showers will be possible across the
Long term /Friday night through Tuesday/...
the low from Canada will approach Friday night into Saturday pulling
increasingly warm and moist air across the area. This will bring a
mostly cloudy sky with some spotty showers possible, especially over
central and northern areas. Showers will be likely Saturday night as
the low tracks east and pulls a cold front through. High pressure
may bring some clearing over the Sunday with clouds and a chance for
showers lingering with the front downeast. The front should then be
far enough south to bring dry weather throughout the region on
Aviation /00z Wednesday through Sunday/...
near term: VFR next 24 hour west/gusty west-northwest winds on Wednesday
approaching 30 kts.
Short term: VFR conditions are expected across the area Wednesday
night through Thursday night. VFR conditions are likely Friday,
but may lower to MVFR over parts of the north late at night. MVFR
conditions in lower clouds are then likely Saturday into Saturday
night. Conditions should return to VFR across the north Sunday but
may be MVFR downeast.
near term: no Small Craft Advisory expected. Winds are forecast to increase west/some
gusts around 20 kts by Wednesday afternoon. Offshore winds will
keep wave heights down below 4 feet.
Short term: conditions may approach Small Craft Advisory in gusts over the
offshore waters Wednesday evening. Otherwise, a light gradient
over the waters should keep winds and seas below Small Craft Advisory through late
week into the weekend.
dry weather will persist through middle week with low relative
humidities. West-northwest winds 15 to 20 miles per hour west/gusts to 35 miles per hour are expected
Wednesday. Collaborated west/gyx and the main Forest service on this
potential. Therefore, a Fire Weather Watch will be up for
Wednesday afternoon into the evening for very high fire danger.
The winds and continued dry conditions with sunshine will cause
high fire dangers into Thursday. Humid air will begin moving into
the area Friday into Saturday.
ME...Fire Weather Watch from Wednesday morning through Wednesday
evening for mez001>006-010-011-015>017-029>032.