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Area forecast discussion...updated 
National Weather Service Jackson MS
925 am CST Wednesday Jan 28 2015

Update...latest satellite imagery show flat upper ridging
developing toward the region from the west with high pressure centered
over the Ohio Valley. Area soundings showed a shallow inversion with
warm air in the low levels. Temperatures will have no trouble pushing into
the 60s for most of the region for this afternoon. Under sunny skies
current forecast looks to be on track with highs from the upper 50s
northeast to around 70 west./17/

/previous discussion...333 am CST Wednesday Jan 28 2015

Short through Thursday night...another warm and dry
day is expected today. Surface high pressure centered over the Ohio
Valley early this morning will shift east to the East Coast by
Thursday morning resulting in a light return flow over our region
this afternoon. The once amplified upper level ridge over The
Rockies on Monday will move over our County Warning Area today in a much dampened
state. Still...ridging surface and aloft today should allow
temperatures to warm into the 60s again this afternoon. Temperatures
Tuesday exceeded guidance and ranged from the upper 50s northeast to
the lower 70s south. Guidance temperatures show little spread today
but appear too cool so have gone several degrees above guidance
across the board. The cool spot will be the northeast again today
topping out near 60 degrees while our western parishes reach 70
degrees again. A shortwave trough and associated surface low will
move over the middle Mississippi Valley by Thursday morning and
continue swinging east through Thursday night. The trailing cold
front will enter our County Warning Area Thursday afternoon. Despite the return flow
this afternoon and ahead of the front Thursday...precipitable waters will only
increase from around a half inch today to just below one inch
Thursday. Model consensus continues to suggest low probability of precipitation of light
showers over our northeast zones Thursday afternoon along the cold
front. Middle and high level clouds will increase ahead of the front
but our south is expected to warm into the lower 70s before the
front moves through. High pressure will build over our County Warning Area in the
wake of the cold front Thursday night ushering in a much cooler and
drier airmass. Precipitable waters will be knocked down to a quarter inch over the
northern half of the County Warning Area by Friday morning. Lows Friday will range
from near freezing in the north to the lower 40s south. /22/

Long term...Friday through next Wednesday...high pressure to the
north skirting the region will result in cooler drier air advecting
back into the forecast area Friday. After highs Friday afternoon
under mostly sunny skies will only climb into the 50s. Lows Friday
night...with clouds increasing from the west through the
night...will fall into the 30s.

Clouds will continue increasing through the day Saturday...with rain
chances beginning to increase early Sunday morning. It'll be from
Sunday morning into Sunday night that the best rain chances through
the long term period will exist. During this time...Pacific
moisture aloft will continue to increase across the lower
Mississippi River valley. As an upper low gets cut off and left to
meander about near the Baja California peninsula...a middle/upper trough will dig
southeast across the nation's mid-section. As this trough swings
east towards the region...a surface low will develop and lift
northwest...dragging a cold front into and through the County Warning Area Sunday
afternoon into Sunday night. This will bring a good coverage of
showers...and perhaps a few thunderstorms to locales primarily south
of Interstate the forecast area throughout the day Sunday
and into Sunday evening. Models continue to indicate that some
potential for heavy rainfall will exist during this time.

Rain chances will end from west to east late Sunday night into early
Monday morning as a much colder drier air filters into the region
behind the cold front. After a dry period Monday and Tuesday...
rain chances again look to creep back into the forecast...
particularly in the south...on Wednesday. This is as a result of
the before mentioned closed low over the Desert Southwest finally
getting pushed east...weakening...and absorbed into a weak
disturbance swinging across the southeast United States. /19/


Aviation...VFR conditions will predominate through the taf period.
Mainly easterly winds this morning will shift around to the south by
tonight...then to the west Thursday afternoon ahead of a weak cold
front. Middle and high clouds will increase ahead of the front early
Thursday...especially at glh and gwo...but ceilings are expected to
remain in the VFR category through the morning. /Dl/


Preliminary point temps/pops...
Jackson 66 45 72 38 / 0 2 8 4
Meridian 62 39 71 37 / 0 2 8 13
Vicksburg 69 49 72 40 / 0 2 7 1
Hattiesburg 67 43 75 44 / 0 2 5 12
Natchez 69 49 74 42 / 0 2 6 4
Greenville 65 48 65 34 / 0 3 10 1
Greenwood 62 45 66 33 / 0 4 12 1


Jan watches/warnings/advisories...



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