000 
fxus62 kmfl 270100 
afdmfl 


Area forecast discussion 
National Weather Service Miami Florida 
900 PM EDT Sat may 26 2018 


Aviation... 
trends in the model suggests more precipitation is possible 
through the night into Sunday. 




&& 


Update... 
raised rain chances overnight to nearly 100 percent as nearly 
certain widespread rain will continue. Latest convective band is 
pushing into far southern Florida nearly 1z and additional banding 
is likely toward early morning. 0z radiosonde observation indicates increasingly 
favorable airmass for rotating updrafts as supplemented by hrrr 
and other cams. Target time for enhanced tornado risk appears to 
be 5z-13z, so will be continuing to closely monitor. Storm Prediction Center continues 
with slight risk of tornadoes and damaging winds south and west of 
a Naples to Miami line overnight, with marginal risk for remainder 
of County Warning Area. Flood Watch and Small Craft Advisory continues areawide. 
High risk of rip currents on East Coast through Monday, with high 
risk Sunday for Gulf Coast. Will be also monitoring for minor 
tidal inundation along the Gulf Coast Sunday, particularly around 
high tide with is roughly midday. A coastal flood statement is in 
effect along the Gulf Coast where a foot or so of inundation is 
possible. Last but not least, Tropical Storm Warning in effect for 
outer Gulf waters, beyond 20 nm offshore. Latest observations from 
buoys in the Gulf and also in and near the Keys should tropical 
storm force wind gusts are likely already occurring in this area. 
8pm NHC advisory on subtropical storm Alberto reveals weak, 
disorganized storm with Max. Sustained winds of 40 mph, though 
highest winds are present well east of the center. Alberto should 
make its closest approach to South Florida during the morning 
Sunday. 


&& 


Previous discussion... /issued 349 PM EDT Sat may 26 2018/ 


Discussion... 
the National Hurricane Center shows Alberto continuing to move north- 
northwestward over the eastern Gulf waters through the rest of the 
weekend. At the same time, an area of high pressure continues to 
remain over the western Atlantic just to the east of the Florida 
Peninsula. This set up will allow for a south southeasterly wind 
flow to continue and it will keep a steady flow of deep tropical 
moisture in place through the Memorial Day weekend. 


With all of this moisture in place, rain chances will remain high 
through the rest of the weekend. Of particular concern is that for 
late tonight and Sunday, South Florida will lie under a region of 
upper-level divergence to the east of the deepening mid/upper level 
low pressure over the Gulf of Mexico associated with Alberto, as 
well as increasing low-level convergence and wind fields around the 
periphery of Alberto's large-scale circulation. This synoptic setup 
is conducive for bands of rain and a few embedded thunderstorms to 
not only increase in coverage but also in intensity as they move 
north across the area. The end result is that our flood threat will 
increase beginning late tonight and continue through Sunday, and 
possibly Sunday night as well. The Flood Watch will remain in place 
at least through Sunday evening, and we will continue to closely 
monitor the threat of heavy rain and flooding even into Monday as 
Alberto continues to affect the northern Gulf Coast. 


Along with the increasing threat of flooding, the potential for 
isolated tornadoes will increase late tonight in response to the 
strengthening low-level wind profiles, helicity values and 
increasing instability. The highest tornado threat appears to be 
late tonight and Sunday over southwest Florida, but notable as well 
over Southeast Florida. This corresponds well with spc's marginal 
risk area over all of South Florida. 


Both of the latest GFS and European model (ecmwf) show Alberto moving across the 
southeastern portion of the country early next week. This should 
also allow for a deep swath of moisture across South Florida as the 
flow should remain out of the south southwest at least through the 
middle of the week. By the end of next week, the swath of deeper 
moisture should slowly move northward out of the region, which 
should allow for a return to a more typical summertime pattern with 
scattered showers and thunderstorms developing along the east and 
West Coast sea breezes. 


Marine... 
the offshore Gulf waters are under a tropical storm watch 
through midday Sunday due to its closer proximity to the outer 
tropical storm force wind field. Wind speeds will be between 25 and 
30 knots across the Gulf waters, with higher gusts even outside of 
any rain bands. Over the Atlantic waters, south-southeast winds of 
20 to 25 knots tonight and continuing through late Sunday. Wind 
speeds gradually decrease to 15 to 20 knots late on Memorial Day, 
except over the offshore Gulf waters where winds will remain around 
20 knots. 


A Small Craft Advisory will be in effect for all the coastal waters 
through at least Sunday night. 


Beach forecast... 
tides have been running about a half-foot above normal along the 
southwest Florida coast based on data from National oceanic and atmospheric administration tide gauges. As 
Alberto moves northward over the eastern Gulf, consensus of the 
latest model guidance shows that the water levels could go up a 
little bit more, as much as 1.5 to 2 feet above mean higher high 
water (mhhw) across portions of the southwest Florida coast during 
the high tide cycle Sunday morning through midday. This will 
allow for the possibility of some minor coastal flooding and minor 
beach erosion especially in the vulnerable areas along the 
Collier County coast. We will continue to monitor this, however if 
this trend continues, a coastal flood statement will need to be 
considered for Sunday. There will be a high risk of rip currents 
along the Atlantic coast beaches through Sunday evening. The 
threat for rip currents will also begin to increase late tonight 
and Sunday along the Gulf Coast beaches, probably to a high risk. 
&& 


Preliminary point temps/pops... 
West Palm Beach 73 83 75 84 / 90 90 60 90 
Fort Lauderdale 75 82 77 83 / 90 90 70 80 
Miami 74 83 75 84 / 90 90 70 80 
Naples 72 84 74 85 / 90 80 60 80 


&& 


Mfl watches/warnings/advisories... 
Florida...Flood Watch through Sunday evening for flz063-066>075-168- 
172>174. 


High rip current risk from 8 am EDT Sunday through Monday 
afternoon for flz069-075. 


High rip current risk through Monday afternoon for flz168-172- 
173. 


Am...Small Craft Advisory until 8 am EDT Monday for amz610-630-650- 
651-670-671. 


GM...Tropical Storm Warning for gmz676. 


Small Craft Advisory until 8 am EDT Monday for gmz656-657. 


&& 






National Weather Service Glossary of Abbreviations
Back to forecast page
Non-Expanded Version (with abbreviations)

Units: English | Metric

Find the Weather for any City, State or Zipcode, or Country:

U.S. State List | Severe Weather | Tropical Storms | Ski Conditions
United States | Canada | Central America | South America | Asia | Europe | Australia | Africa | Islands

Weather Underground

© Copyright 2018
The Weather Company, LLC