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Area forecast discussion 
National Weather Service Jackson MS
805 PM CDT Friday Jul 3 2015

Update...a line of thunderstorms currently extends from near
Columbus southwest to just north of the metropolitan this evening and is
working its way to the east. Some of these storms have been strong
to severe this evening with some reports of quarter to Golf Ball
sized hail. Expect this line to continue to move east through the
evening hours mainly staying north of the I-20 corridor. Hi-res
models indicate that we may get a short break from the
thunderstorms later this evening...but the global and hi-res models
indicate that thunderstorms will redevelop over the northern portions
of the area out ahead of a strong short wave very early on Saturday.
With a very moist airmass and training storms flash flooding may
become an issue. This has already been highlighted in the graphicast
and severe weather potential statement. The current forecast looks on track and no updates are
needed at this time./15/

Short term...tonight through Saturday night...it has been a quiet
day for the most part with much of the rain and storms remaining
north of my County Warning Area. This has caused significant flooding issues across
portions of northern MS while further south there has yet to be any
rain. This is in association with a stalled frontal boundary north
of the region and storms have been training through the day in
mostly unidirectional flow. As disturbances rotate in the upper flow
in the base of the upper trough...additional storms have been able
to push to southeast from generally the arklatex region and are now
moving into the north and northwestern sections of my County Warning Area. They are
moving into an environment with decent low level lapse rates...shear
and instability. This has allowed some to become strong to severe
with wind gusts and some hail being the primary risks. As this
activity continues to swing south and east this afternoon and
evening...global and hi-res models indicate that another disturbance
will move south later tonight and this one could stall across a
portion of the area. Models are in general agreement that this could
lead to potential for flooding in locations along and north of I-20
through tonight. Precipitable water values are shown to be near 2 inches across
northern areas...336-340k Theta-E air...strong moisture transport
into the region and...in unidirectional flow and very weak corfidi
vectors...this could lead to some localized heavy rain of 2-3
inches(or potentially greater in some locations)/flooding issues
especially given any storms that backbuild/train across the region.
Limited risk areas in the severe weather potential statement and graphics seem reasonable and have
left them in tact.

The million dollar question is what will the weather be on
Independence day. Unfortunately...it wont be nearly as nice as it
was last year when a cold front came through and brought unseasonably
drier air into the region. In this rather complex...northwest flow
regime...it really is hard to pinpoint just what is going to evolve.
If the expected band of showers/storms develops later tonight...this
could linger into early tomorrow. Hi- res models seem to indicate
that this will slowly sag south through the day tomorrow and affect
southern sections of the County Warning Area during the afternoon and evening
hours...which is certainly not good news for fireworks and outdoor
activities. It is likely best to say that both the GFS and European model (ecmwf) show
another disturbance moving through the region and this will likely
combine with any daytime heating/outflow boundaries/differential
heating boundaries/moist airmass to produce additional showers and
thunderstorms particularly during the later afternoon and evening
hours. There is the risk for any of these storms to become strong to
severe with lightning and damaging wind gusts to be the primary
concerns. It is best for residents to keep updated with the latest
weather information especially when planning to be outdoors.

Temperatures during this period will be a little below normal as
clouds and rain should keep some areas...mostly in the north...into
the lower to middle 80s. Outside of storms...temperatures during the day
will reach into the upper 80s and lower 90s.



Long term...Sunday through next work week...anomalously suppressed
upper level troughing for early July (and the attendant sagging
frontal zone in our region) will finally lift back to the north
later Monday into Monday night. However...before the regime
changes...expect a good deal of showers and thunderstorms Sunday and
Sunday night (and then becoming increasingly focused in northern and
eastern zones on monday). These periods will have to be watched for
hazardous weather threat although wind shear and moisture transport
will be declining by this point and thus the confidence of any
severe storms or flooding problems is too low to include in the severe weather potential statement
quite yet. Of course the clouds and showers will keep temperatures
down below normal in most areas on Sunday although heat will be
trying to increase from the southwest on Monday.

Model agreement on increased subtropical ridging influence for
Tuesday through the remainder of next work week is now pretty good.
There are still uncertainties on how much afternoon shower and
thunderstorm activity will occur despite ridge suppression...but the
consensus idea is that precipitation over this period will be below
average. Fortunately...moist soils in many areas will work against
temperatures spiking upwards quickly in reaction to the changing
weather regime. However...expect heat to build gradually through the
middle to late week with plenty of humidity to push peak afternoon heat
index values up to near the century mark. /Bb/

&&

Aviation...mainly VFR conditions this afternoon at the taf sites.
Expect thunderstorms to spread east-southeast into the area late this
afternoon into the evening with additional activity overnight. Storms
will cause local reductions in ceilings and visibility. /SW/

&&

Preliminary point temps/pops...
Jackson 73 85 70 87 / 77 63 60 60
Meridian 71 85 68 87 / 72 70 62 59
Vicksburg 74 85 71 88 / 69 67 58 58
Hattiesburg 74 87 71 87 / 27 53 55 61
Natchez 74 86 71 89 / 33 68 58 56
Greenville 73 85 70 89 / 97 66 56 60
Greenwood 73 85 70 87 / 97 63 51 58

&&

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

$$

28/bb/SW

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