Orlando Hamcation Final Final Weather Forecast

[Thomas F. Giella NZ4O]

Date Max/Min Temp Rain Chance

Fri 12th- 51/39 90%
Sat 13th- 53/34 30%, rain ending by around 6:00 am
Sun 14th- 58/27

Take Care,
Thomas F. Giella
Retired Meteorologist
Lakeland, FL, USA
meteorologist at tampabay.rr.com

Amateur Radio C/S NZ4O
NWS Tampa Bay Skywarn #POL-10A
NWS-APRS-CWOP #AR692/NZ4O
CoCoRaHS #FL-PK-18

Florida Weather Discussion: http://www.floridaweatherdiscussion.com
Lakeland, FL Daily Climatological Weather Data Archive: 
http://www.lakelandfloridaweather.com
Lakeland FL Weather Observations: http://www.thomasfgiella.com
Florida & U.S. Raw Weather Forecasting Resource Links: 
http://www.wcflunatall.com/nz4o13.htm
Harmful Man Induced Climate Change (Global Warming) Refuted: 
http://www.globalwarminglie.org



#10 Published Thursday February 11, 2010 at 2:00 pm EST at 
http://www.floridaweatherdiscussion.com

Well I have been mentioning the possibility of some frozen precipitation 
across portions of north Florida since Sunday 2/7. Well having said that I'm 
not even sure where to begin with this discussion/forecast.
It could be a reputation maker or buster for any Meteorologist, especially a 
retired and rusty one like myself. After looking at the latest weather 
forecast model runs, the current synoptic situation and some climatology, I 
guess that I'll just jump into the doo doo straight away.

Parts of north Florida could see a record breaking measureable snowfall 
event during the next 24-36 hour period. When one looks at the overall deep 
layered synoptic pattern, though it may seem to defy the laws of physics, it 
looks probable that a weak to moderate strength surface extra-tropical low 
pressure system will form along the central Texas coast and move due east or 
even ESE towards the Florida peninsula.

It could cross the peninsula west to east as far north as say Sarasota to 
Ft. Pierce or as far south as say Everglades City to Ft. Lauderdale. 
Normally climatology would argue against such a low latitude track but 
during a moderate to strong El Nino it does happen.

Snow could break out late Thursday evening-Early Friday morning 2/11-12 
beginning at Pensacola and then moving ENE-ward to near Marianna and points 
northward to the Florida-Alabama state line. Measureable snow of 1-3" is 
possible in this zone and if you believe the latest NAM forecast model, 
upwards of 5-6" of snow could fall.

Of course I'm not forecasting that kind of snowfall event as the most snow 
ever officially observed in the panhandle west region is 4.0" at Milton and 
a couple of other locations. However unofficial amounts of 5-8" did fall 
north of Pensacola in February 1973 and again in March 1993.

It appears as though the winter storm will be a two part scenario, with 
flakes falling from Pensacola to the Apalachicola River Thursday night into 
Friday morning and then further eastward on Friday evening and Saturday 
morning 2/12-13. A mix of rain and snow could fall as far east as 
Tallahassee before sunrise on Friday morning with no accumulation. Then a 
mix of light rain and snow could fall along a line between Monticello to 
Jasper to Fernandina Beach and points northward Friday evening-Saturday 
morning. A flake or two could also fall as far south as a line say from 
Cross City to Gainesville to St. Augustine.

What ultimately happens depends on the strength and track of the surface 
extra-tropical low pressure system. Weak surface lows are more conducive to 
snow in north Florida, as warm air advection in the SE-E quadrants of the 
storm is weaker to nearly non existent.

During the day on Friday maximum temperatures could hover in the low to mid 
30's across the panhandle west region and mid 30's to low 40's across the 
non peninsula north region. With temperatures hovering in the low to mid 
40's, a significant rainfall event could occur across portions of the north 
and central peninsula region. It would be an isentropic lift (warm moist air 
lifted over a shallow cold air mass) rain.

Once again depending on the track of the surface extra-tropical low pressure 
system, the weather across the south central peninsula could range between 
the 50's and rain to 60's and rain, with possibly some thunderstorms. The 
south peninsula weather could range between temperatures in the 60's with 
rain, with possibly a few thunderstorms to temperatures in the 70's with 
thunderstorms, some of which could be severe.

There will be plenty of high (>300 m2s-2) helicity (vertical spin) values. 
The saving grace against severe weather would be the lack of low level 
instability and therefore lack of thunderstorm formation.

That's my .05 cents on the issue now due to inflation. I will continue to 
monitor the situation as the day progresses.

Take Care,
Thomas F. Giella
Retired Meteorologist
Lakeland, FL, USA
meteorologist at tampabay.rr.com

Amateur Radio C/S NZ4O
NWS Tampa Bay Skywarn #POL-10A
NWS-APRS-CWOP #AR692/NZ4O
CoCoRaHS #FL-PK-18

Florida Weather Discussion: http://www.floridaweatherdiscussion.com
Lakeland, FL Daily Climatological Weather Data Archive: 
http://www.lakelandfloridaweather.com
Lakeland FL Weather Observations: http://www.thomasfgiella.com
Florida & U.S. Raw Weather Forecasting Resource Links: 
http://www.wcflunatall.com/nz4o13.htm
Harmful Man Induced Climate Change (Global Warming) Refuted: 
http://www.globalwarminglie.org