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fxus64 kjan 051729 aaa 

Area forecast discussion...updated
National Weather Service Jackson MS
1129 am CST Thu Dec 5 2019

updated for 18z aviation discussion


18z taf discussion:
VFR conditions will prevail at all sites throughout the day today.
Then expect some lowering ceilings early tomorrow morning after
09z due to low clouds moving in with this system. With this,
-ra will also become increasingly likely from west to east. /Jne/


quiet weather will persist through today as a high pressure is
still centered over much of the arklamiss. Some high clouds are
building in currently in the west but won't be of any concern for
today. Not much needed to be changed, the previous forecast was
very much on track. Highs will be in the upper 60s for most of
the area and near 70s in the southwest./Jne/

Prior discussion below:

Today through tonight: forecast guidance has not wavered much in
showing a that a shortwave trough will approach the area later
today and tonight. Developing return flow will bring milder
temperatures and increasing clouds, but shower chances are not
expected to increase in earnest until close to daybreak Friday.
Convective instability should be just enough to support getting a
few storms by that time, and moisture transport could support a
few heavy downpours, but no significant impacts are expected with
rainfall totals generally less than an inch on average given the
progressive nature of the system. /Ec/

Friday through next wednesday: as we begin the period Friday, the
previously mentioned shortwave trough will be in the process of
shifting east southeast across the Ozarks and through the forecast
area during the course of the day. At the surface, this will
result in a surface low developing and racing east southeast into
and across the forecast area from early Friday morning into Friday
evening. Showers, along with a few isolated storms, will likewise
spread across the County Warning Area during this time, with rain chances ending
over eastern portions of the forecast area late Friday night.

Behind this system, northwest flow will again advect a slightly
cooler drier airmass into the region for the first half of the
upcoming weekend. The aforementioned system looks to hang-up over
the north central Gulf of Mexico Saturday. A series of subtle
disturbances aloft will traverse the region, as the once stalled
system washes out, and the remaining moisture associated with it
gets pulled northward across Alabama. This could potentially bring
an isolated shower or two to portions of east and southeast
Mississippi Sunday and Sunday night.

As we start the new work week, a broad trough will drop southeast
out of the intermountain west into the Great Plains Sunday night
into Monday. This will result in flow aloft across the County Warning Area
increasing, in addition to an increase in isentropic upglide ac.
Ross the region. This will bring an increase in rain chances across
the forecast area Monday.

These rain chances will persist into Tuesday as the trough swings
east through the region. This will push a cold front southeast into
and across the forecast area overnight Monday into Tuesday. Rain
chances will gradually come to an end Tuesday night. High pressure
will build back into the County Warning Area Wednesday from the northwest, resulting
in a return to cooler drier conditions. /19/


Preliminary point temps/pops...
Jackson 68 51 68 48 / 0 36 90 18
Meridian 68 47 67 49 / 0 23 85 30
Vicksburg 71 54 69 47 / 0 44 81 12
Hattiesburg 68 48 72 51 / 0 21 71 36
Natchez 70 54 72 51 / 0 31 58 11
Greenville 66 52 64 45 / 0 74 100 10
Greenwood 66 52 63 46 / 0 61 100 14


Jan watches/warnings/advisories...


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