Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

fxus64 kjan 191613 aaa 
afdjan

Area forecast discussion...updated
National Weather Service Jackson MS
1013 am CST sun Feb 19 2017

Update...
updated for morning discussion.

&&

Discussion...
morning low clouds and fog have, for the most part, dissipated.
However, some low clouds are lingering in the west/southwest part
of the forecast area. Where sunshine is occurring, temperatures
have warmed nicely into the upper 60s. Elsewhere, some upper 50s
or lower 60s are still evident. Temperatures this morning are
running about 5 to 12 degrees warmer than this time yesterday and
we are on track for a rather warm day. Upper ridging has taken
residence over the arklamiss and this, along with plentiful
sunshine, should allow for an unseasonably warm day with highs in
the upper 70s and lower 80s. Some locations, especially in the
western half of the County Warning Area could see records tied or possibly broken.
Going forecast is in decent shape and adjustments were made to
expire the dense fog advisory and remove rest of fog from the
forecast, as well as, account for current trends. /28/

Prior discussion below:

Today and tonight:
so far overnight, fog development has been slow to occur, but it
is finally taking place mainly across the southern third of the
County Warning Area. We are also seeing reduced visibilities at a few sites
farther north around the Golden Triangle. With winds calm in most
areas and limited cloud cover to inhibit radiational cooling, fog
is likely to continue expanding over the next several hours. At
this point we'll keep the current dense fog advisory configuration
but expand the limited dense fog threat in the severe weather potential statement/graphics to
include the remainder of the area. We'll also closely monitor
observational trends to determine if an expansion of the advisory
is necessary later this morning.

Once fog and low clouds dissipate, we should warm up quickly
today as an anomalous mid/upper level ridge builds over the
region. Given this, we went above guidance Max temps for today
with lower 80s for most of the south half of the area. For
tonight, surface winds will begin to pick up a touch more over
the western half of the area as the gradient gradually tightens
ahead of the next storm system. However, it appears they will
remain light enough farther east for some patchy fog development
during the overnight hours. /Dl/

Monday through Saturday night:

An unseasonably warm weather pattern will continue over the forecast
area this week. Rainfall will be mostly confined to the Monday night-
Tuesday time frame with additional shower chances possible late in
the week.

A rather amplified shortwave trough will shift slowly east across
the Southern Plains and eventually cut off from the westerlies as it
approaches the arklamiss Monday into Monday night. Very moist air
exceeding 1.5 inches of precipitable water will be drawn northward
ahead of the closed low into northeast la and southwest MS late
Monday night into Tuesday. The combination of the slow-moving system
and very moist air will promote the potential for locally heavy
rainfall, but the lack of instability and deep convection will tend
to keep rainfall rates from becoming intolerable. Will continue to
monitor southwest portions of the forecast area for any flooding
potential and hold off on including any such threat in the
hwo/graphics. As the upper low begins a more southerly trek into the
Gulf of Mexico Tuesday night and Wednesday, expect better
lift/moisture convergence to shift south bringing the end to any
heavy rain threat.

Shortwave ridging will bring a return to dry weather during the
middle of the week with above normal temperatures, especially
Thursday. The next shortwave trough expected to approach Friday will
not be as amplified and will not have as much time for return flow
to moisten up the airmass sufficiently for getting much rainfall.
Moreover, it looks like the airmass will be capped and unsupportive
of thunderstorms. Expect cooler temperatures more typical of late
February to follow the associated cold front. /Ec/

&&

Aviation...
12z taf discussion:
conditions this morning range from VFR at glh/gwo to LIFR at
hbg/gtr as areas of fog develop across the area. Further expansion
of IFR/LIFR conditions is possible across the southern and eastern
portions of the area, with most fog dissipating by mid morning.
Additional fog and low stratus development is possible late
tonight into early Monday morning, especially across south MS.
Otherwise, VFR conditions are expected through the remainder of
the taf period. /Dl/

&&

Preliminary point temps/pops...
Jackson 82 56 81 59 / 0 0 5 44
Meridian 79 53 80 56 / 0 0 4 19
Vicksburg 81 56 81 60 / 0 0 9 61
Hattiesburg 81 54 81 58 / 0 0 4 28
Natchez 81 59 80 61 / 0 0 16 67
Greenville 79 55 78 58 / 0 0 8 54
Greenwood 78 56 80 58 / 0 0 6 40

&&

Jan watches/warnings/advisories...
MS...none.
La...none.
Arkansas...none.

&&

National Weather Service Glossary of Abbreviations