341 
fxus62 kkey 210115 
afdkey 


Area forecast discussion for the Florida Keys 
National Weather Service Key West Florida 
920 PM EDT Sat Mar 20 2010 


Discussion... 
currently... 
kbyx detects no precipitation echoes. Skies over the island chain 
are mostly clear. Winds over land are northeast to east near 10 miles per hour. 
C-man winds...on average...are northeast to east near 15 knots. 
Temperatures are near 70 degrees. 


Short term (overnight)... 
a cold front will move eastward across the western and central Gulf 
of Mexico overnight. Farther east...an Atlantic ridge of high 
pressure over North Florida will retreat eastward tonight. The 00z 
kmfl sounding is very stable and dry for this time of year...with a 
precipitable water (pwat) value just above three quarters of an 
inch. Atmospheric moisture will increase across the Florida Keys 
tonight. By sunrise Sunday...precipitable water values in the Florida Keys will be 
just under one and one quarter of an inch. Despite this anticipated 
increase in atmospheric moisture...the very stable air mass in place 
will be responsible for no chance of rainfall tonight. 


&& 


Marine... 
small craft are urged to exercise caution on Atlantic waters 
overnight due to sustained east to southeast surface winds of 15 to 
20 knots. Small craft are urged to exercise caution on Atlantic 
waters Sunday morning due to sustained southeast surface winds of 15 
to 20 knots. Winds will decrease and seas will subside on all Keys 
coastal waters Sunday afternoon. A cold front will pass across the 
Florida Keys Sunday night...causing winds to shift to northwest. A 
Small Craft Advisory for hazardous seas will likely be required for 
deep Gulf waters and Atlantic waters west and south of Cosgrove 
Shoal light Monday and Monday night. A Small Craft Advisory for 
hazardous seas may be required for deep Gulf waters and Atlantic 
waters west and south of Cosgrove Shoal light Tuesday. No advisories 
or cautionary statements expected Tuesday night through at least 
Thursday. 


&& 


Aviation... 
VFR conditions will prevail overnight at the island terminals. Clear 
skies will become partly cloudy as stratocu move in from the 
southeast. Surface winds will start out east around 10 knots...then 
turn more southeast and become gusty. 


&& 


Climate... 
on this date in Keys weather history...in 2003...the low temperature 
at Key West International Airport was 79 degrees. This set the 
record for warmest low temperature ever recorded in Key West during 
the month of March. 


&& 


Equipment... 
upper air soundings from Key West should resume on March 22nd at 
12z. Thermodynamic data may be estimated from the Miami and/or Grand 
Cayman soundings. Winds aloft may be estimated from the cudjoe 
profiler and kbyx/kamx VAD wind profiles. 


&& 


Key watches/warnings/advisories... 
Florida...none. 
GM...none. 


&& 


$$ 


Public/marine/fire/digital/climate...bs 
aviation.............................11 


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