textproduct: Miami - South Florida

KEY MESSAGES

Updated at 800 AM EDT Thu Mar 12 2026

- Rain chances increase later today and will remain elevated through the weekend as a couple areas of low pressure and a weakening frontal boundary approach South Florida.

- Temperatures will remain above normal through the weekend.

UPDATE

Issued at 800 AM EDT Thu Mar 12 2026

Fog over interior portions of the southern Florida peninsula this morning should burn off shortly after 9 AM.

Otherwise, the current forecast remains on track for today as low-level S-SW wind flow gradually increases in moisture. Although the main forcing with the front across North Florida should remain north of our region, isolated to scattered showers are expected this afternoon as the east coast sea breeze sets up over the east coast metro areas. In addition, scattered afternoon showers are expected over portions of SW Florida well in advance of the frontal system. Rain chances remain in the 20-30% range this afternoon, with the main time frame between 1-8 PM. Surface- based CAPE is forecast to increase into the 1400-1700 j/kg range over SE Florida this afternoon, driven by temperatures rising into the mid/upper 80s and dewpoints in the upper 60s/around 70F, providing just enough instability to support one or two thunderstorms. However, these should not reach strong levels due to general lack of deep moisture/shear.

NBM-based QPF values are generally under a quarter of an inch through this evening, with reasonable high-end amounts up to a half-inch in spots and max LPMM values around 1 inch.

SHORT TERM

(Today through Friday) Issued at 125 AM EDT Thu Mar 12 2026

The surface high pressure located over the western Atlantic and the stout mid-level/upper-level ridge will begin to be forced away from the area by an approaching potent shortwave trough expected to sweep through late today. This shortwave is modeled to get absorbed into the large scale trough covering most of the central and eastern US as it advects across the Florida Peninsula for the end of this week. Surface flow will shift to the south and then southwest throughout today as the trough begins to propagate across the Florida Peninsula. This flow pattern will allow for some warm and moist air to be advected across the region, but the deepest moisture is expected to remain north of the area in the central Florida region at least for today. The attendant cold front with this trough will force the deeper moisture southwards on Friday morning before the front stalls out near the Lake O area due to a lack of a temperature gradient. As a result of this and being on the periphery of surface high pressure, any shower and embedded thunderstorm activity that develops later today is expected to be fairly lackluster and not pose major hazards.

By Friday afternoon as the deeper moisture ushers into the region, rain chances increase to around 40-60% with a higher likelihood of some widespread showers and storms. However, the upper level pattern will be weakening and thus additional forcing will be lost for this moisture to take advantage of. Model soundings also highlight a fairly deep dry air layer above 700mb, likely capping the potential vertical development of any convection. Nevertheless, sea breeze development in the afternoon along with diurnal heating processes should be enough to produce some pretty widespread showers and storms on Friday. The strongest enhancement of convection is expected to occur along these sea breeze boundaries as a weak flow pattern sets up behind the departing trough. The specifically strongest individual storm cells will form where the strongest low-level convergence occurs, which is likely to be over inland/interior locations given the weak flow. As for severe storm potential, these are not expected due to the drier air aloft inhibiting deep convective growth as mentioned previously.

In terms of potential rainfall totals, QPF for both days individually to end the week are not higher than 0.25-0.5 inches and the HREF LPMM through Thursday night does not indicate potential for QPF to total more than 0.5-0.6 inches either. Therefore, while any rainfall will be welcomed given the ongoing drought, overall rain accumulations are not expected to cause any hydro concerns. High temperatures each day will be in the mid to upper 80s with overnight lows in the 60s except for the east coast metro which will hover around 70 degrees.

LONG TERM

(Friday night through Wednesday) Issued at 125 AM EDT Thu Mar 12 2026

Deeper moisture will remain pooled over South and Central Florida for several days as the incoming front will not be strong enough to force the moist air out of the area. With this setup involving a lingering weak front, weak surface high pressure replacing the departing trough, and model soundings suggesting substantial dry air above the 700mb layer, overall instability is not expected to be high although it will be enough to support some thunderstorm development each day through the weekend and into early next week especially as another shortwave trough looks to sweep across the area in the Sunday-Monday time frame. The daily sea breeze circulations and any thunderstorm outflow boundaries will pose potential for additional rounds of rain. QPF each day is still forecast to be no more than about half an inch each day in an average sense across the region. While localized areas can see much more than this, this pattern does not favor consistent heavy bouts of rain. Specific rainfall amounts will be refined in the coming days as guidance becomes more clear, but right now looks like 72- hour rainfall potential sits in the 1-2 inch range between Saturday morning and Tuesday morning.

For early next week, long term ensemble guidance continues to suggest the potential for a stronger frontal boundary trying to reach the area. This front may very likely get stalled out as well towards the middle of next week, but uncertainty remains with this. Right now, it looks like drier air has a good chance to advect into the region with dew points falling 5-10 degrees towards the middle of next week and decreasing PoPs. These trends will continue to be monitored to determine if this front will be able to force some of the abundant low level moisture out of the area.

High temperatures will continue to be in the low to mid 80s or even upper 80s for some interior locations each day through Monday of next week. Beyond that into the middle of next week, temperatures have a chance to fall back into the 70s. Overnight lows will be in the 60s each night through Monday night for most areas, although east coast locations will continue to be around 70.

AVIATION

(12Z TAFS) Issued at 800 AM EDT Thu Mar 12 2026

Prevailing VFR conditions, although with occasional and brief BKN ceilings in the 2000-2500 ft and 4000-5000 ft range mainly MIA- PBI corridor through 00z. Scattered SHRA developing 18z-21z over these same areas, with VCSH indicated for the time being. An isolated TS not out of the question. Wind 180-210 degrees gusting over 15 knots through 18z, then shifting to 140-160 degrees from 18z-00z.

MARINE

Issued at 125 AM EDT Thu Mar 12 2026

A moderate southeast breeze over the Atlantic waters today will shift southerly to south-southwesterly as a disturbance approaches the area. Meanwhile, a gentle southwesterly breeze will occur over the Gulf waters. Lighter and more variable winds are then expected heading into the weekend with a return to an easterly flow becoming established during the weekend. Rain chances will increase beginning late today as a frontal boundary and its associated disturbance approach the area. Scattered showers and storms are expected each day beginning late today. Seas are expected at 2 feet or less through Friday morning, but will rise for portions of the Atlantic on Friday as the disturbance progresses across the region.

BEACHES

Issued at 125 AM EDT Thu Mar 12 2026

The risk for rip currents will rise again by this weekend as winds shift back to an onshore direction, but a very low risk exists for today as winds shift offshore for a day.

PRELIMINARY POINT TEMPS/POPS

Miami 85 71 83 71 / 20 30 40 30 West Kendall 88 67 85 66 / 10 20 40 20 Opa-Locka 87 70 84 69 / 20 30 50 30 Homestead 86 70 84 70 / 10 20 40 30 Fort Lauderdale 84 70 82 69 / 20 30 50 30 N Ft Lauderdale 85 70 82 70 / 20 30 50 30 Pembroke Pines 87 70 84 70 / 20 30 50 30 West Palm Beach 87 70 81 69 / 30 40 40 30 Boca Raton 86 70 82 69 / 30 40 40 30 Naples 84 68 84 69 / 30 30 30 20

MFL WATCHES/WARNINGS/ADVISORIES

FL...None. AM...None. GM...None.