NWS Technical Forecast Discussion


Observed at
Lowell, Massachusetts
18-Jan-2018 11:00 AM

Temperature

23.6°F

Hour Change

1.6°F

Humidity

82%

Hour Change

-2%

Dewpoint

18.9°F

Hour Change

1.0°F

Wind

6 mph from 316° (NW)

Wind Gust

13 mph

Barometer

29.944 inHg

3 Hour Trend

-0.016 inHg

Today's Rain

0.01 in

Rain Rate

0.00 in/hr

Rain Last Hour

0.00 in

Monthly Rain

0.86 in

Yearly Rain

0.86 in

Wind Chill

16.2°F

Heat Index

23.6°F

Today Highs / Lows

High Temperature

Low Temperature

28.9°F at 12:00 AM

16.2°F at 07:43 AM

High Humidity

Low Humidity

95% at 12:00 AM

81% at 10:52 AM

High Dewpoint

Low Dewpoint

27.7°F at 12:00 AM

13.8°F at 07:43 AM

High Barometer

Low Barometer

30.048 inHg at 12:00 AM

29.942 inHg at 10:50 AM

High Wind Gust

13 mph from 355° at 10:49 AM

High Rain Rate

0.00 in/hr at 12:00 AM

Low Wind Chill

9.9°F at 07:57 AM

High Heat Index

28.9°F at 12:00 AM

Yesterday's Statistics

High Temperature

Low Temperature

32.8°F at 12:33 PM

28.9°F at 11:55 PM

High Humidity

Low Humidity

95% at 08:33 AM

87% at 12:00 AM

High Dewpoint

Low Dewpoint

31.4°F at 11:55 AM

27.7°F at 11:55 PM

High Barometer

Low Barometer

30.386 inHg at 12:06 AM

30.047 inHg at 11:59 PM

High Wind Gust

9 mph from 19° at 12:11 PM

Rain

0.06 in

High Rain Rate

0.00 in/hr at 12:00 AM

Low Wind Chill

23.4°F at 11:56 PM

High Heat Index

32.8°F at 12:33 PM

000
FXUS61 KBOX 181136
AFDBOX

Area Forecast Discussion
National Weather Service Taunton MA
636 AM EST Thu Jan 18 2018

.SYNOPSIS...
Dry and seasonably cold conditions today and Friday, then a
warming trend this weekend with continued dry weather. A storm
system will affect the region sometime Monday night into Tuesday
with mostly rain and coastal wind, but there is a risk of some
mix/ice across the interior. Blustery and colder weather follows
next Wednesday.

&&

.NEAR TERM /THROUGH TONIGHT/...
630 AM update...
Still some lingering low clouds across the Cape/Islands which
may persist for a few hours per low level RH fields. Meanwhile,
area of high clouds streaming north along the south coast,
ahead of coastal low to the south. These clouds should move
offshore by midday, otherwise lots of sunshine today across
SNE.

Expect temps to only reach the lower-mid 20s across the E
slopes of the Berkshires, ranging to the lower-mid 30s across
the coastal plain.

&&

.SHORT TERM /FRIDAY/...
Tonight and Friday...

As the H5 cutoff low finally pushes offshore tonight, NW winds
will diminish as the surface ridges builds E across the region.
Skies will remain mainly clear early.

Noting another H5 short wave in the fast flow out of the Great
Lakes, which will cross the region around or after midnight.
Little if any moisture with this system, and what there is should
pass across northern New England overnight. Will see mid level
clouds move across, then start to lift NE toward daybreak. May
see some brief lower clouds across portions of NW Mass during
the pre dawn hours. Expect lows mainly in the teens, ranging to
the lower-mid 20s along the coast.

The short wave will quickly push to the Maritimes Friday
morning, taking the clouds with it though some scattered high
clouds may linger across central and N Mass during the day.
Winds will be mainly W, so expect temps to run close to seasonal
normals, topping off in the upper 20s to lower 30s across
central and western areas, ranging to the mid 30s along the
coast.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
Highlights...

* Dry and mild this weekend
* Another storm will bring mostly rain and gusty coastal winds
  Mon night/Tue with a risk of some interior mixed precip/ice

Mild and dry conditions expected this weekend under zonal flow
and rising heights. Temps should reach well into the 40s both
days with the chance of a few 50 degree readings Sat. It will
be a bit breezy Sat with potential for 25-35 mph SW gusts near
the coast which will temper the milder temps but less wind
Sunday.

Some light precip in the form of rain/snow showers possible Mon
in the developing warm advection pattern, but models have
trended a bit slower with timing of next storm, with greatest
impact likely sometime late Mon night into Tue. Deep mid level
trough/low approaching from the west is expected to lift NE
across the Gt Lakes and into SE Canada. A robust pre-frontal low
level jet will likely bring a decent slug of rain to SNE with
potential for heavy rainfall and strong coastal wind. PWAT and
low level wind anomalies are 2+ SD which is pretty good for a
day 5-6 forecast. Exact timing of the rain and wind is uncertain
and there also remains enough uncertainty with thermal profile
that some interior mix/ice possible at the onset. ECMWF is more
robust with the colder air but it will take awhile for these
finer details to be resolved.

As storm exits, blustery and colder weather will likely follow
next Wednesday.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
Forecaster Confidence Levels...

Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.

Short Term /through Friday/...High confidence.

Today...VFR. May see some lingering MVFR CIGS across the mid
and outer Cape and well as KACK through 14Z before improving.
NW winds gusting up to 20 kts along the immediate S coast, Cape
Cod and the islands this afternoon.

Tonight...Mainly VFR conditions. May see some local MVFR CIGS
at times across the outer Cape and E slopes of the Berkshires
on N-NW winds.

Friday...VFR conditions for most areas, but may see MVFR CIGS
linger across the E slopes of the Berkshires through midday.

KBOS Terminal...High confidence in TAF.

KBDL Terminal...High confidence in TAF.

Outlook /Friday Night through Monday/...

Friday Night: VFR. Breezy.

Saturday: VFR. Windy with gusts to 30 kt.

Saturday Night: VFR. Breezy.

Sunday through Sunday Night: VFR.

Monday: MVFR/IFR conditions possible. Chance SHRA.

&&

.MARINE...
Forecaster Confidence Levels...

Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.

Short Term /through Friday/...High confidence.

Expect NW winds around 10 kt or so today, then will back to W
and remain light tonight and Friday. Seas will continue at
around 5 ft across the open waters through today at least. They
should subside on the eastern outer waters late tonight, but
will continue on the southern waters. Small Craft Advisories
remain in effect there.

Outlook /Friday Night through Monday/...

Friday Night: Low risk for Small Craft Advisory winds with
local gusts up to 30 kt. Seas up to 5 ft.

Saturday: Low risk for gale force winds with gusts up to 35 kt.
Rough seas up to 11 ft.

Saturday Night: Low risk for Small Craft Advisory winds with
gusts up to 30 kt. Local rough seas.

Sunday: Winds less than 25 kt. Seas locally approaching 5 ft.

Sunday Night: Winds less than 25 kt.

Monday: Winds less than 25 kt. Seas locally approaching 5 ft.

&&

.HYDROLOGY...
A Flood Warning remains in effect for the Connecticut River at
Middle Haddam, where ice jams are causing river fluctuations.

Cold conditions will persist through Thursday which will limit
additional runoff. Continued ice jams will remain on some of the
rivers. There will be some increase of snow pack across
interior southern New England as well.

For details on specific area rivers, including observed and
forecast river stages, please visit the Advanced Hydrologic
Prediction Service (AHPS) graphs on our website.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory until 6 AM EST Friday for ANZ250.
     Small Craft Advisory until 6 PM EST Friday for ANZ254>256.

&&

$$
SYNOPSIS...KJC/EVT
NEAR TERM...KJC/EVT
SHORT TERM...EVT
LONG TERM...KJC
AVIATION...KJC/Dunten/EVT
MARINE...KJC/Dunten/EVT
HYDROLOGY...

NWS BOX Office Area Forecast Discussion