Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Gray ME
1235 am EDT Friday Sep 19 2014
high pressure will build in from the west tonight through Friday
and will shift offshore Friday night. High pressure will remain
off the East Coast Saturday allowing a warm front to track
northeast across the area Saturday night. A cold front will
quickly follow from the west Sunday night into Monday...and will
provide a round of showers. High pressure will build in behind the
front Monday night through Wednesday.
Near term /until 6 am this morning/...
1225 am...just tweaking the mins for this morning a bit based on
current observation. In the mountains and foothills...where most ob sites are
reporting calm or very light winds temperatures are generally in the
30-35 range at this time...and most spots should get into the upper 20s to
around 30. The coastal plain is a bit more problematic as still
seeing many sites with winds of around 4-8 miles per hour /or more/...and
temperatures in the 40s. Some sheltered spots...which have decoupled...will
frost out easily...but may not see quite the coverage in the
advisory area...unless the gradient suddenly relaxes.
strong cold air advection will be working into the region this evening behind a
cold front. Skies should clear after sunset and temperatures will
plummet shortly after...giving US our coldest temperatures this
season and most likely ending the growing season for all of our
northern forecast zones. Coldest temperatures will be across the
north where pressure gradient will be weaker. In the south as the
high pressure move in the gradient will tighten and this will keep
winds up overnight. Current thinking is that low lying sheltered
locations along the coastal plain will see a frost
tonight...however most of the area will be spared...so just went
with frost advisories in these areas. Coastal zones and interior
Rockingham County should escape seeing frost as winds will remain
strongest in these locations overnight.
Short term /6 am this morning through 6 am Saturday/...
high pressure will be overhead tomorrow and although we will have
plenty of sunshine...it is still going to be quite cool since most
areas will start off in the upper 20s to low 30s. The high will
shift off shore on Friday afternoon and southwest flow will
develop. T850 will continue to warm through Saturday morning and
will be a solid 10c warmer than they were Friday morning. Fog will
most likely develop in the valleys on Friday night under the clear
and calm conditions.
Long term /Saturday through Thursday/...
high pressure moves off the coast Sat and Sat night allowing a return
warmer southwest flow to develop ahead of an approaching upper
trough and associated surface cold front. Scattered showers will develop in
the mountains Sun afternoon and spread south over the rest of the forecast area Sunday
night ahead and then along this cold front...not a lot of quantitative precipitation forecast
will be associated with the front. Behind the front for early
next week a return to cooler and mainly fair weather except maybe a few
showers in the mountains
By midweek and beyond a major blocking high pattern develops
allowing the beginning of a very long nice stretch of dry weather.
Aviation /06z Friday through Tuesday/...
short term...mostly VFR conditions expected through the entire
period except for fog conditions in the valleys...dropping hie and
leb down to LIFR conditions in the early morning hours.
Long term...mainly VFR through Sunday...although some valley fog
possible each night. Some MVFR conditions possible late sun
through Sun night in scattered rain showers ahead in advance of a cold front.
short term...winds will increase tonight behind the cold
front...with scas expected for all the outer waters. Things will
start to calm down by late Friday morning and no further flags are
Long term...SW flow ahead of cold front could bring winds and seas
to Small Craft Advisory criteria Sat night and Sunday.
ME...freeze warning until 8 am EDT this morning for mez007>009-
Frost advisory until 8 am EDT this morning for mez018>022.
New Hampshire...freeze warning until 8 am EDT this morning for nhz001>006.
Frost advisory until 8 am EDT this morning for nhz007>010.
Marine...Small Craft Advisory until 10 am EDT this morning for anz150-