UREGNT SEVERE WEATHER UPDATE FORECAST SYNOPSIS…SEVERE WEATHER OUTBREAK POSSIBLE ACROSS PARTS OF THE LOWER MISSISSIPPI RIVER VALLEY ON SATURDAY…ISSUED DEC. 20, 2013…8:45 P.M…PHFC

DONATIONS NEEDED
Funny dog holds dollars in mouth, isolated white background

Good evening everyone!

The Storm Prediction Center, Norman, OK. has issued a MODERATE risk of Severe Thunderstorms  FROM EAST TEXAS ACROSS MUCH OF LOUISIANA…SOUTHEAST ARKANSAS…WESTERN TENNESSEE AND ALL OF WESTERN MISSISSIPPI…

THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MDT RISK AREA FROM EAST TX THE UPPER TX GULF COAST NORTHEAST TO THE OH RIVER VALLEY…TN VALLEY AND NORTHERN GULF COAST… .
..SEVERE WEATHER OUTBREAK POSSIBLE ACROSS PARTS OF THE LOWER MISSISSIPPI RIVER VALLEY ON SATURDAY…

SPC DAY 2 CONVECTIVE OUTLOOK

CURRENT SPC PROBABILISTIC OUTLOOK
Probability of severe weather within 25 miles of a point.  Hatched Area: 10% or greater probability of significant severe weather within 25 miles of a point.

Analysis this afternoon and evening of forecast severe weather sounding parameters indicates the greatest threat for severe thunderstorms will lie within the 30% probability area in the probabilistic map.

The greatest threat for tornadic activity appears to lie within the hatched area.  Based on analysis of the GFS and NAVGEM solutions of various severe weather parameters based on F5 Data severe weather software, including but not limited to forecast lifted indices, SWEAT Index, Storm Relative Helicity, Craven- Brooks values, etc.  the severe event could initiate as early as 8 – 9 a.m. CDT.  The area with the greatest risk for tornadoes, possibly EF2 -EF3 from approximately 9 a.m. to 12 p.m. EST is outlined in blue in the following map:
day2otlk_1730 TR 9-12

The following outline depicts the possibility from 12 p.m. to 3 p.m. EST
day2otlk_1730 TR 12-3

After this time frame, based on the probability that the atmosphere will most likely remain conducive for severe weather overnight, as the threat shifts North and East, the likelihood for severe weather is outlined in blue, with tornadic activity a possibility early in the period outlined in orange, then after 6 p.m. EST over the portion circled over Ohio.
day2otlk_1730 6-12EVE

Ingredients at the time of analysis indicated a vigorous LLJ (Low Level Jet), Mid level jet, and a fairly strong Jetstreak in the upper levels.  Ample humidity is also forecast at the low and mid levels of the atmosphere.  Wind shear, both directional and speed should provide enough helicity for rotational supercells.

10 METER WINDS AND PRECIPITATION
gfs_namer_021_10m_wnd_precip

850 MB LEVEL WINDS AND JET
gfs_namer_024_850_rh_ht

500 MB LEVEL WINDS AND JET
gfs_namer_018_500_rh_ht

250 MB JETSTREAM AND JETSTREAK
gfs_namer_018_250_wnd_ht

Bear in mind, this current synopsis is based on information analyzed late this afternoon, and some things will most likely change by tomorrow.

I will analyze severe weather index parameters again in the a.m., as well as morning soundings from around the risk areas, particularly in the MODERATE risk area, and will try to update before noon time.  The possibility could exist for this to become a PDS, however I will make this determination after completion of analysis in the morning.

Have a blessed evening!

T. F. “STORM” WALSH III 
GMCS, USCG (ret) 
METEOROLOGIST / HURRICANE SPECIALIST 
MEMBER WEST CENTRAL FL AMS  
CERTIFIED SKYWARN OFFICIAL STORM SPOTTER (advanced) 
CoCoRaHS OBSERVER

Advertisements

About palmharborforecastcenter

I am a Tropical Forecast meteorologist, providing hurricane forecasts during the Atlantic Hurricane Season. I retired from the U.S. Coast Guard in July of 2001. Meteorology became my passion in high school, and I have continued my educational background in meteorology since 1996, when I undertook the study of Tropical Meteorology. While working toward my degree, I had to unexpectedly withdraw from college due to my oldest sons medical reasons. I do however, meet the educational criteria of the AMS to be recognized as a meteorologist. Studies include, but are not limited to the Navy Aerographers Mate course, Naval METOC meteorology course, Meteorology 2010 Sophomore level course while attending St. Petersburg College, Clearwater, FL., Basic Forecasting course for operational meteorologists from Rapid WX, meteorology institute, a four month meteorological internship, and extensive research on numerous meteorological topics such as the MJO, NAO, satellite imagery interpretation, etc. I have been forecasting Tropical Weather (Tropical Storms and Hurricanes) since 1996, with my main client being three different Coast Guard Commands.
This entry was posted in Severe Weather. Bookmark the permalink.

4 Responses to UREGNT SEVERE WEATHER UPDATE FORECAST SYNOPSIS…SEVERE WEATHER OUTBREAK POSSIBLE ACROSS PARTS OF THE LOWER MISSISSIPPI RIVER VALLEY ON SATURDAY…ISSUED DEC. 20, 2013…8:45 P.M…PHFC

  1. originallt says:

    Thanks Storm.

  2. Mike Doll says:

    Thanks Storm! Ill pay attention to this tomorrow afternoon through Sunday morning. We here in LA( lower Alabama) need to pay attention.

  3. Thanks, Storm, for the “Urgent” notification. Both my “homebase” and my present “holiday” location are “just” to the W of the hatched areas, but we S and Central Texans are glad that we have a valuable source keeping us informed. We’ll keep our eyes peeled.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s