Discussione scientifica sulle previsioni

NWS Discussion
			
				

Area forecast discussion...updated 
National Weather Service Miami Florida 
937 am EDT Wednesday may 22 2013 


Update 2...trough of low pressure over the Florida Peninsula 
will continue to move slowly east into the western Atlantic waters 
today. This will allow for a little bit of drier air to work into 
the area from the Gulf of Mexico. However...the east and West 
Coast sea breezes will develop today and push inland. The West 
Coast sea breeze will push across the area today with the East 
Coast sea breeze remaining near the East Coast metropolitan areas due to 
the south to southwest steering flow over the area. 


So the showers and thunderstorms over the Atlantic waters this 
morning should dissipate by noon time with showers and 
thunderstorms developing over the land areas. So will keep the 
scattered to numerous probability of precipitation over South Florida for this afternoon. 


There could also be a few strong storms over the interior and East 
Coast metropolitan areas this afternoon into early this evening. The 
primary impacts from the strong storms will be gusty winds...heavy 
rainfall...and small hail. So will continue to mention this in the 
morning severe weather potential statement package. 


Rest of the forecast looks good at this time and no other changes 
are planned. 


&& 
Update...54/bnb 




Previous discussion... /issued 719 am EDT Wednesday may 22 2013/ 


Aviation...scattered showers will continue this morning across the eastern 
portions of the peninsula with terminals kmia...kopf and ktmb 
possibly having brief periods of MVFR ceilings. There is a lingering 
middle to upper level trough and available tropical moisture that is 
expected to enhance chances of convection today with all terminals 
assigned thunderstorms in the vicinity at 15z except for terminal kapf assigned at 16z. For 
all terminals brief periods of IFR conditions may be possible with the 
stronger thunderstorms by the early afternoon. 


&& 


Previous discussion... /issued 523 am EDT Wednesday may 22 2013/ 


Update...showers have recently increased over the Atlantic with 
movement onshore the coast. Some are becoming heavy with even a 
thunderstorm in far South Miami-Dade with a few lightning strikes 
detected. Given the radar trends and hrrr depiction, have increased 
weather to numerous for all of the East Coast and interior through 
this afternoon. /Gregoria 


&& 


Previous discussion... /issued 356 am EDT Wednesday may 22 2013/ 


Discussion...a middle-upper trough just off the Atlantic coast will 
get picked up and merged by a long wave trough moving across the 
Great Lakes. Moisture and instability continues sufficient today 
to allow for scattered to numerous showers and thunderstorms to 
develop. Hrrr is showing numerous activity this afternoon. The 
focus of thunderstorms looks to be across the interior and to the West 
Palm Beach metropolitan area. A few strong thunderstorms are possible with 
locally heavy rains this afternoon given residual cold air aloft 
as well as some upper level divergence especially across Palm 
Beach County. However, middle level temperatures will slowly be warming 
through the day. Still, we will highlight a few strong thunderstorms in 
the hazardous weather outlook. 


The trend Thursday and into the weekend is a drying one with less 
and less shower and thunderstorms activity expected. This is the result 
of the local area being east of a building ridge over the Gulf and 
west of the departing trough which will promote subsidence. That 
being said, there still looks to be the potential for scattered 
afternoon thunderstorms along the Atlantic coast on Thursday, and 
isolated thunderstorms Friday. The tail end of a cold front pushes into 
Florida on Friday. This front dissipates and a strong surface high 
builds into the eastern U.S. Over the weekend. Friday looks hot 
ahead of the dissipating front with lower 90s most locales. Then 
over the weekend it turns breezy on a northeast wind as the strong 
high moves into the Ohio Valley with a tighter pressure gradient 
locally. The northeast wind is forecast to lower dewpoints into 
the middle 60s this weekend, possibly even lower 60s making it feel 
nice...especially along the Atlantic coast where temperatures will be 
slightly cooler than the Gulf Coast along with a stronger wind. 


For next week, moisture will slowly increase as winds turn east to 
southeast, leading to an increasing chance of daily showers and 
thunderstorms. However, no significant weather features are in the 
offing. 


Marine...winds will be on the decrease this morning then rather 
light winds will prevail through Friday before winds turn 
northeast and increase over the weekend with a corresponding 
increase in seas, especially over the Atlantic. Swan is generating 
seas of up to 5 feet over the Atlantic this weekend. 


Fire weather...no concerns as relative humidities remain above 
critical levels. 


&& 


Preliminary point temps/pops... 
West Palm Beach 86 72 87 73 / 60 40 30 20 
Fort Lauderdale 86 74 88 76 / 60 40 30 20 
Miami 87 74 89 76 / 60 40 30 20 
Naples 86 71 86 72 / 30 10 10 10 


&& 


Mfl watches/warnings/advisories... 
Florida...none. 
Am...none. 
GM...none. 
&& 


$$ 


Discussion/marine/fire...54/bnb 
aviation/radar...17/era