Scientific Forecaster Discussion

Return to Local Conditions & Forecast
Area forecast discussion 
National Weather Service Taunton Massachusetts
202 PM EDT Thursday Apr 24 2014

windy and dry conditions today...then winds diminish tonight and
Friday as high pressure builds into the region. Low pressure will
bring rain Friday night into Saturday...then mainly dry and
seasonable conditions Sunday into Monday as high pressure returns.


Near term /until 7 PM this evening/...

2 PM update...

Not much change from previous update with northwest winds gusting
up to 45 miles per hour. The exception was Nashua with a gust to 51 miles per hour
/44kt/. Thus Wind Advisory remains in effect until 7 PM. Temperatures
climbing into the mu50s except low 50s higher terrain. Few
locations will likely touch 60 briefly later this afternoon across
eastern Massachusetts and Rhode Island including Boston to Providence.


Short term /7 PM this evening through 6 PM Friday/...
gusty winds lingering into the evening...then winds diminish as
pressure gradient relaxes with high pressure approaching from the
west. Clear skies and diminishing wind will result in a cold night
with mins middle 20s to lower 30s across much of the region...except
upper 30s bos/pvd and Outer Cape/islands.

high pressure moves across new eng then to the east by days end. Next
shortwave will be lifting NE from the Ohio Valley which will
result in an increase in middle/high clouds in the afternoon from the
west. It will remain dry as deep moisture transport associated with
the low level jet remains to the west through 00z. It will be a
milder day in developing warm air advection pattern. Soundings
show mixing to 850 mb where temperatures increase to 2-3c around 18z.
This supports temperatures into the low and middle 60s...but 50s along the S
coast due to southerly wind.


Long term /Friday night through Wednesday/...

* unsettled but seasonable weather Friday night into Saturday
* uncertainty higher than normal for next week

24/00z models are in decent agreement through much of the long term.
There are of course some discrepancies towards the end of the
period. A double barreled low pressure system will affect
southern New England Friday night and Saturday with some
uncertainty in how close the southern low moves to the southern
New England coast. The European model (ecmwf) is farthest from the coast...passing
over the 40/70 benchmark and the NAM is closest passing over
Nantucket. The European model (ecmwf) has trended north since the 12z run so went
with a NAM/GFS blend for this portion of the forecast. Beyond
this...models are struggling with a developing blocking pattern.
Models are quick to move towards a more progressive pattern.
Ensembles show the blocking pattern a bit better though there are
differences amongst the members as to whether we will be more
influenced by ridging or troughing. Between this and the models
tendency to rush a return to a more progressive pattern...have a
lower confidence than normal for next week.

Friday night and Saturday...double barrel low pressure moves east
across southern New England. The northern low moves through Quebec
while the southern low passes south of southern New England. The
European model (ecmwf) is the farthest south with the southern low while the NAM is
the farthest north. Expect scattered showers across southern New
England with this system. Steep middle level rates provide enough
instability for thunderstorms to occur and as such have mentioned
thunder in the grids.

Sunday into early next stated above a more blocked pattern
looks to develop with middle level troughing over the NE bringing
unsettled weather to the region. Where exactly the blocked pattern
sets up will determine what sort of weather we are looking at. Some
models have a pronounced easterly flow which would result in
unseasonably cool temperatures and overcast skies across much of the
area. However...a shift could result in more seasonable weather.


Aviation /18z Thursday through Tuesday/...
low...less than 30 percent.
Moderate...30 to 60 percent.
High...greater than 60 percent.

Short term /through 12z Saturday/...high confidence

Through 00z...gusty northwest winds 30-40 knots continue then beginning to
diminish around sunset. VFR as well.

After 00z...VFR with a diminishing wind.

Friday...VFR with light winds...seabreezes along the coast.

Friday night...VFR to start then quickly lowering to MVFR with
rain overspreading western CT/Massachusetts 00z-06z then into Rhode Island and eastern
Massachusetts 06z-12z. Low risk of IFR toward 12z Sat. East-southeast winds
may increasing up to 25 knots toward 12z Sat across Rhode Island and eastern

Kbos terminal...high confidence in taf.

Kbdl terminal...high confidence in taf.

Outlook...Saturday through Monday...

Moderate confidence. Mainly VFR. Brief periods of MVFR/IFR
conditions in rain showers/fog.

Sunday and Monday...low confidence. VFR.


forecaster confidence levels...

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

Short term /through Friday/...high confidence.

10 am update...

No major changes from previous forecast. Strongest winds near
shore given warmer land temperatures /55-60/ than ocean temperatures /low 40s/.
Earlier discussion below.

Northwest gales expected through today with gusts to 35-40 knots. Winds
diminish through tonight as gradient relaxes with light winds on
Friday as high pressure moves across the waters.

Outlook...Friday night through Monday...

Friday night and Saturday...low to moderate confidence. S winds
and seas increase as a cold front approaches the waters.
Visibilities may be reduced at times in rain showers. Small craft
advisories may be necessary on the outer waters. Winds shift to
the northwest as the cold front crosses the waters.

Sunday and Monday...moderate confidence. North/northwest winds and seas
generally remain below small craft criteria but conditions are
close. Small craft advisories may be needed.


Fire weather...
10 am update...

No major changes from earlier discussion. Previous forecast
matching up nicely with current conditions.

Conditions today are favorable for fire weather headlines with
min relative humidity 15-25 percent and strong wind gusts to 40 miles per hour.
However...recent rainfall in central and eastern new eng will
preclude red flag conditions in these areas. However...less
rainfall occurred in the CT valley and after collaboration with
okx/aly we have decided to issue a red flag warning for north CT.


Box watches/warnings/advisories... flag warning until 8 PM EDT this evening for ctz002>004.
Massachusetts...Wind Advisory until 7 PM EDT this evening for maz004>007-
New Hampshire...Wind Advisory until 7 PM EDT this evening for nhz011-012-015.
Rhode Island...Wind Advisory until 7 PM EDT this evening for riz001>007.
Marine...Gale Warning until 8 PM EDT this evening for anz230>237-250-


near term...kjc/nocera/rlg
short term...kjc
long term...rlg
fire weather...