AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FORT WORTH TX
1037 PM CST TUE FEB 9 2010
.UPDATE...
REGARDING THE WEDNESDAY NIGHT THROUGH THURSDAY EVENING STORM
SYSTEM...BASED ON ANALYSIS OF 00Z MODEL DATA DID NOT MAKE ANY
SIGNIFICANT FORECAST CHANGES. AS PREVIOUS FORECAST PACKAGE
INDICATED MOST RECENT GUIDANCE IS WARMER IN NATURE AND WOULD
THEREFORE FAVOR MORE LIQUID PRECIPITATION FOR THE EVENT. BASED ON
FORECAST SOUNDINGS A NEARLY ISOTHERMAL LAYER EXISTS BETWEEN THE
H925 AND H800 LAYER WHERE THE TEMPERATURE HOLDS RIGHT AROUND 0 DEG
C. NEARLY ALL GUIDANCE INDICATES THAT SFC TEMPS WILL BE NEAR OR
ABOVE FREEZING THRU MUCH OF THE EVENT IN NORTH TX...SO
PRECIPITATION TYPE WOULD SEEM TO DEPEND ON THE TEMPERATURES IN
THIS FAIRLY DEEP ISOTHERMAL LAYER ALOFT. IF TEMPS HOLD RIGHT
AROUND 0 DEG C...A SNOWFLAKE/LIQUID RAINDROP MIX WILL LIKELY FALL
INTO THE WARMER NEAR SFC LAYER AND MOSTLY RAIN WILL FALL. IF THIS
ISOTHERMAL LAYER HOLDS CLOSER TO -2 DEG C NEARLY ALL SNOWFLAKES
WILL ENTER THE WARMER NEAR SFC LAYER AND MOSTLY WET SNOW WOULD
FALL. 00Z GUIDANCE WOULD POINT TO A MOSTLY COLD RAINFALL
EVENT...WITH MAYBE SOME BETTER CHANCE FOR SNOW NEAR THE RED RIVER.
FOR CONTINUITY WILL LEAVE THE RAIN/SNOW MIX IN THE FORECAST FOR
NOW AS RELATIVELY SMALL TEMPERATURE CHANGES IN THIS ISOTHERMAL
LAYER ALOFT WILL HAVE A BIG CHANGE ON POTENTIAL WINTER WEATHER
IMPACTS AND CHANCES FOR ACCUMULATING SNOWFALL. IF 06 AND 12Z
MODELS CONTINUE TO TREND WARMER OR REMAIN NEARLY IN LINE WITH 00Z
GUIDANCE COULD PROBABLY REDUCE CHANCES OF A RAIN/SNOW MIX IN FAVOR
OF A MORE LIQUID FORECAST.
ONLY CHANGES WERE TO UP POPS A BIT FROM 12Z THURSDAY - 06Z FRIDAY
AS MEASURABLE PRECIPITATION LOOKS LIKELY DURING THE PERIOD.
BROUGHT SNOWFALL AMTS DOWN A BIT GENERALLY OVER THE METROPLEX. NOW
HAVE SNOWFALL ACCUMULATIONS CLOSER TO 1 INCH AS OPPOSED TO THE 1-2
INCHES IN THE PREVIOUS FORECAST. WILL NOT BE ISSUING ANY HEADLINES
ATM AS THE 1 INCH SNOWFALL LOOKS TO BE FAIRLY WET AND WOULD NOT BE
EXPECTED TO ACCUMULATE ON MUCH MORE THAN GRASSY SFCS. A COLDER
SOLUTION WOULD WARRANT HIGHER SNOWFALL AMTS AND PROBABLY SOME SORT
OF WINTER WEATHER HEADLINE. FOR NOW...MOST RECENT GUIDANCE POINTS
TO A LOW IMPACT WINTER WEATHER EVENT BUT WE WILL CONTINUE TO
MONITOR THE EVOLUTION OF THIS SYSTEM CLOSELY.
CAVANAUGH
Hey more power to them if they hold on and end up being right, however I so want them to be wrong.....

Don't hold me accountable for anything I post on this forum. Leave the real forecasting up to the professionals.
Location: Ponder, TX (all observation posts are this location unless otherwise noted)