Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

fxus64 kjan 181155 aaa 

Area forecast discussion...updated
National Weather Service Jackson MS
655 am CDT Wed Oct 18 2017


Updated for 12z aviation discussion.



12z taf discussion:
VFR conditions will prevail through Thursday morning. /22/



Today and tonight:

Continued dry and slightly warmer. Early morning surface analysis
had a 1028mb high centered over the central Appalachians and
ridging back across the Gulf Coast states. Early morning water
vapor imagery/rap analysis showed the flow over a 590dam high
centered over southern Texas. The mid level ridge will strengthen
over our region while the surface high remains in place through
Thursday morning. This will lead to a continuation of dry weather
and warmer temperatures today and tonight. The 00z Wed Jan
sounding had a precipitable water of 0.38in. Pwats will remain below a half inch
through tonight. Under a light wind and full insolation of our
dry airmass again today, temperatures will top near normal. Under
clear skies and a near calm wind again tonight, strong radiational
cooling of our dry airmass will lead to morning lows slightly
cooler than normal. /22/

Thursday through tuesday:

Quiet and warm weather will continue through the end of the week
as an upper-level ridge translates eastward across the southern
U.S. Then our attention quickly turns to a deepening trough of low
pressure moving from the West Coast towards the central Continental U.S. Over
the weekend. The primary upper-level low center looks to remain
over interior Canada during this timeframe, but guidance has been
consistently showing a sharp shortwave and attendant surface cold
front reaching the Mississippi River valley by Sunday or Monday.
However, model guidance continues to show poor run-to-run
consistency regarding the trough after it crosses the Rocky
Mountains. At various times the GFS, ECMWF, and CMC have indicated
a portion of the trough energy to close off and develop a low
center over the Gulf Coast late in the weekend or early next week.
This continues to be the case with the latest round of guidance,
so the regional forecast attempts to split the differences.

Regardless of exactly how the pattern evolves over the next few
days, showers and thunderstorms will likely affect the arklamiss
area beginning Saturday as moisture returns from over the Gulf of
Mexico. And rain chances will continue through at least Sunday
night if the trough remains an open wave. If a closed low
develops, expect warmer and wetter weather to continue into
Monday or Tuesday. The GFS currently represents the slowest
solution that keeps a chance for wrap-around precip through
Tuesday. A reinforcing cold front should bring cooler and drier
weather heading into the middle of next week. /Nf/


Preliminary point temps/pops...
Jackson 78 49 82 54 / 0 0 0 0
Meridian 77 46 80 52 / 0 0 0 0
Vicksburg 79 48 82 54 / 0 0 0 0
Hattiesburg 77 49 81 54 / 0 0 0 0
Natchez 78 51 81 56 / 0 0 0 0
Greenville 78 47 80 52 / 0 0 0 0
Greenwood 77 46 80 53 / 0 0 0 0


Jan watches/warnings/advisories...


National Weather Service Glossary of Abbreviations