Area forecast discussion
National Weather Service Mount Holly New Jersey
617 PM EDT Wednesday Jun 19 2013
Synopsis...
high pressure from the Great Lakes will spread into the northeast
and Middle Atlantic States, before moving east and offshore on
Thursday. Another area of high pressure from southeastern Canada is
then forecast to build over our region Friday before moving offshore
on Saturday. A return southwesterly flow around this high pressure
will then likely take shape over our area, bringing increasing
warmth and humidity into early next week.
&&
Near term /through Thursday/...
dry northwest flow aloft and high pressure building in at the surface will
continue to provide fair weather over the forecast area. Some diurnal cumulus
noted this afternoon as well as cirrus over delmava associated with frontal zone
now far to our south. These clouds should mostly dissipate or slide
off to the southeast by evening.
Sea breeze and Bay breeze are noted over southern New Jersey both on radar and
vsbl satellite. The sea breeze is forecast to make its way across New Jersey into
southeast PA by around 7-8 PM.
For tonight...clouds will clear and winds will drop off...and surface
dewpoints continue to drop some into the 40s or lower 50s south. Conds are
quite favorable for radiative cooling overnight...especially away
from urban areas. Forecast mins in the 40s north and 50s south represent
a 20 to 30 degree f drop from this afernoons maximum temperatures. Some patchy fog
is possible late tonight but it should not be widespread.
&&
Short term / Thursday through 6 am Thursday/...
high pressure overhead tonight will shift offshore for Thursday.
This will result in light/variable winds in the morning becoming light S
to south-southwest in the afternoon. However there will be little or no moisture
retunr so conds should remain pleasant. Maximum temperatures Thursday should be
similar to today except perhaps a couple degrees warmer generally north
of phl. 850 mb temperatures show a slight increase.
&&
Long term /Thursday through Wednesday/...
5-wave model guidance shows the eastern trough beginning to finally
lift towards the northeast though it looks like we will keep a
pseudo-zonal flow aloft...though it has a higher latitude. Western
Atlantic ridging will retrograde across the southeastern United
States middle of the period which will help to amplify the flow
aloft and introduce a bit more unsettled weather through the
remainder of the longterm.
Surface and low-level ridging look to really build over the region
on Friday and Saturday before slowly receding back towards the
east-southeast. Looks of sinking air will be taking place giving US
mostly clear skies and precipitation free. We will have a pretty
weak surface flow from the southwest but there will be a slight
increase in moisture. Low-level temperatures begin to climb as the
core of low-level ridging moves across the region so we can expect
daytime highs reaching into the low to mid-80s. By Sunday the
surface and middle-level ridging will be moving off to our southeast
and a stronger return flow kicks in. 850mb temperatures climb into
the middle to upper teens in spots equating to daytime highs close to
90f from Monday through the remainder of the longterm.
This return flow will really bring the humidity back into the
region. Dewpoints will be climbing into the upper-60s at the same
time multiple middle-level waves traverse across the top of the
ridging. This increases our chances at seeing showers and
thunderstorms from late this weekend through the end of the
longterm. Most of this convective activity should be diurnally
driven and wane during the late evening hours.
&&
Aviation /22z Wednesday through Monday/...
the following discussion is for kphl, kpne, kttn, kabe, krdg, kilg,
kmiv, kacy and surrounding areas.
Good flying conds expected for at least the next couple of days. VFR
conds now observed at all our taf sites...and expected to continue
tonight and Thursday. Light NE winds this afternoon will become
light/variable this evening through overnight into Thursday morning...then
light southerly/southwesterly Thursday afternoon. One exception is the sea breeze moving
westward across southern New Jersey...which could affect ilg/phl/pne/ttn by around 6
to 8 PM this evening with briefly higher southeast winds.
Outlook...
Friday - Saturday...MVFR or lower possible in early morning fog/haze.
VFR with light southerly winds.
Sunday - Monday...mostly VFR with MVFR or lower in morning
fog/haze and then again in possible in scattered showers/thunderstorms
during the afternoon hours.
&&
Marine...
generally light winds/seas are forecast for at least the next day or
two. Building high pressure and associated NE winds over the waters have
resulted in seas flirting with Small Craft Advisory conds over the southern area vicinity
buoy 44009. However winds are expected to become lighter this evening
and overnight so seas should begin to subside.
High pressure moving offshore on Thursday will bring winds around to
the south by afternoon. A seabreeze noted today will likely
re-develop tomorrow afternoon with asscd locally onshore flow.
Outlook...
sub-advisory conditions will persist across our waters through the
outlook period. Seas will be around 3 feet with light southerly
winds slightly veering towards the southwest by Sunday.
&&
Rip currents...
there is a moderate risk of rip currents in New Jersey today.
&&
Phi watches/warnings/advisories...
PA...none.
New Jersey...none.
Delaware...none.
Maryland...none.
Marine...none.
&&
$$
Synopsis...Heavener
near term...amc
short term...amc
long term...Heavener
aviation...amc/Heavener
marine...amc/Heavener
rip currents...
climate...
