Area Forecast Discussion
Issued by NWS Miami, FL
Issued by NWS Miami, FL
Versions:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
478 FXUS62 KMFL 201134 AFDMFL Area Forecast Discussion National Weather Service Miami FL 734 AM EDT Mon May 20 2024 ...New AVIATION... .SHORT TERM... (Today through Tuesday) Issued at 115 AM EDT Mon May 20 2024 A positively-oriented mid-lvl trough will remain draped across the western Atlantic through the short-term period, with several lower amplitude shortwaves pivoting southward into our area on its western periphery. The main surface feature of interest will be relatively weak low pressure positioned just northeast of the area, and the weak cold front associated with this system which will gradually push through our area today into Tuesday. Given the proximity of the weak synoptic boundary, weak ascent ahead of the trough, and potentially the east coast sea breeze, expect scattered to numerous storms to develop this afternoon with the focus largely being the east coast given the sea breeze and orientation of the trough. The convective parameter space is not as conducive as yesterday due to weaker mid-lvl lapse rates and weaker deep-layer shear, but another day of rather warm temperatures will result in steep low-lvl lapse rates/high DCAPE values. Consequently individual cell wet microbursts will remain a threat along with small hail due to seasonably cool air aloft. Although temperatures will still be well above average in the prefrontal regime (highs in the low to mid 90s), slightly drier air should keep us below heat headline criteria (although maximum heat indices will exceed 100 degrees over most of the area). The front will largely have worked its way through the area by Tuesday, and surface flow will generally begin to veer more east- northeast through the day. Rain chances will remain elevated as a trailing shortwave pivots into the area, with at least scattered storms likely igniting along the two sea breezes (with the northeast winds tending to favor southern portions of the area). Temperatures will drop into the upper 80s and lower 90s which while still a few degrees above average, may actually feel pleasant after the mid-May heatwave. && .LONG TERM... (Tuesday night through Sunday) Issued at 115 AM EDT Mon May 20 2024 By the mid-week period, the mid-level shortwave propagates to the east of the region over the western Atlantic waters. 500mb flow over South Florida will veer to a northerly direction ushering in reinforcing dry air across the region. At the surface, ridging situated over the southeastern United States will allow for relatively light winds across the region. Thus with a lack of synoptic support, mesoscale patterns such as the sea-breeze circulation will dictate temperatures as well as the most probable locations for convective initiation and coverage. Typical thunderstorm hazards such as heavy rainfall and gusty winds will be possible but cannot rule out isolated strong to severe pulse storms that are able to take advantage of the localized maximized ascent along boundary collisions even in the background of a fairly benign pattern. Benign weather will continue for much of the long-term period as surface ridging remains firmly in place and synoptic features remain to the north of South Florida. With the advection of the surface ridge to the east, easterly surface flow across the region will remain dominant. This will act to feature the hottest temperatures across southwestern Florida for the time being as the Atlantic sea- breeze is able to traverse further inland. High temperatures will range from the upper 80s to low 90s across the east coast of South Florida to temperatures in the low to mid 90s across southwestern Florida. Although heat indices will be less oppressive then the past couple of days, heat safety precautions should still be followed, especially for vulnerable populations. && .AVIATION... (12Z TAFS) Issued at 729 AM EDT Mon May 20 2024 Generally VFR conditions for all TAF sites today, although sub-VFR conditions are possible for East Coast sites this afternoon as SHRA/TSRA develop near the area. W-SW winds 8-12 kts will prevail today, but some East Coast sites could see the sea breeze intruding after 18-19Z, resulting in a E-SE wind shift. Light and variable winds overnight as conditions improve, with more easterly winds possible tomorrow across much of the area. && .MARINE... Issued at 115 AM EDT Mon May 20 2024 Generally benign conditions should prevail across local waters through the period. Winds will trend more W-NW today as a weak front crosses the area and then more easterly in the mid-week period. Scattered to numerous showers and thunderstorms will be expected today and potentially Tuesday. Storm chances will decrease in the mid-week period as high pressure builds near the area. && .PRELIMINARY POINT TEMPS/POPS... Miami 92 76 88 75 / 50 30 50 50 West Kendall 94 73 90 73 / 40 20 50 40 Opa-Locka 94 75 89 75 / 50 30 50 40 Homestead 94 75 89 75 / 30 30 50 50 Fort Lauderdale 91 75 87 76 / 60 30 50 50 N Ft Lauderdale 92 74 87 75 / 60 40 40 40 Pembroke Pines 94 75 91 76 / 50 30 40 40 West Palm Beach 92 73 87 73 / 40 30 40 40 Boca Raton 92 74 88 75 / 50 30 40 40 Naples 90 74 91 74 / 20 10 20 20 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. GM...None. && $$ SHORT TERM...Carr LONG TERM....Carr AVIATION...ATV