textproduct: Melbourne

KEY MESSAGES

Issued at 203 AM EDT Sun Mar 15 2026

- Numerous showers and storms will impact the area later today and Monday. A few storms could become strong or severe, with a 5-10% chance for damaging winds up to 60 mph and quarter-size hail.

- Beneficial rainfall is expected, but repeated storms may lead to minor flooding in urban areas.

- A strong cold front moves through Monday night, bringing gusty winds and hazardous boating conditions. Much cooler air arrives Tuesday morning, with lows falling into the 40s across the Orlando and Daytona Beach areas.

DISCUSSION

Issued at 203 AM EDT Sun Mar 15 2026

-----------Synoptic Overview-----------

A split flow regime continues this morning, with Florida sitting just north of the subtropical jet. Across the northern Rockies, a 170 kt H3 polar jet streak is beginning to carve out a longwave trough that will drive a blizzard across the Upper Midwest and severe weather across the Mid-Mississippi Valley.

The initial approach of this sharpening trough has turned mid-level winds southwesterly over Florida. Within the subtropical jet, a weak impulse of energy over the western Gulf is expected to move over the state this afternoon and evening. As it does, it will encounter moderate to strong instability, courtesy of cool H5 temps (~ -13 deg C) above a warm, moist boundary layer. Proximity soundings reveal 2000+ J/kg of SFC CAPE, sufficient downdraft CAPE, and weak but veering wind profiles yielding around 20 KT of effective shear.

As the unusually deep longwave trough over the Central U.S. migrates eastward, a surface cold front is expected to reach the Florida Peninsula on Monday afternoon. Deep-layer shear is expected to increase to 30-35 kt as southwesterly winds increase ahead of the front. PW values from 150-175% of mid-March norms will persist until the front passes, supporting 1500-2000 J/kg of SFC CAPE during peak heating.

Much drier and cooler air filters in behind the front on Monday night. Ensemble-averaged H925 (~ 3 kft) temperatures fall to between +3 and +9 deg C on Tuesday afternoon, which is near the 5th percentile for the time of year.

The 13/12Z grand ensemble is coming into somewhat better agreement with the pattern from mid to late next week, but the details are still a bit murky. The polar jet is expected to quickly retreat northward, but Florida will sit downstream of a strong H5 ridge and unprecedented March heatwave over the Desert Southwest for much of the week. With the PNA turning positive, this is likely to leave a weak mid-level trough somewhere near the state. This feature should interact with a baroclinic zone to produce a surface trough or an area of low pressure by around Thursday, particularly near or just offshore of South Florida.

With Central Florida sandwiched between a potential surface trough and continental high pressure to the north, onshore breezes are expected to freshen from mid to late next week. This will yield some temperature moderation but also allow for some moisture to return. Expect a sharp gradient of moisture over the southern half of the state through at least Thursday.

By next weekend, another trough will enter the Northeast U.S., likely kicking much of this moisture out to sea. Temperatures are expected to continue moderating as west-northwest flow aloft pulls eastward some of the unusually warm air over the Western U.S.

-------Sensible Weather & Impacts-------

Today - Tonight...

A bit of patchy fog may form early this morning over the interior. Aside from a rogue shower or two, most of the area should remain on the quiet side through midday. That will quickly change by afternoon as the ingredients come into place for a round of numerous showers and storms (70-90%). The 14/18Z REFS suggests that storms are most likely between 2 PM and 9 PM today, with north-northeastward storm motions.

You will need to stay aware of the weather today. The entire area is in a 5-10% SPC Marginal Risk for gusty winds of 50-60 mph and coin-size hail up to quarters, perhaps slightly larger. AI/ML convective outlooks support these probabilities.

Convective-allowing ensembles indicate that locally heavy rain is possible as well, with a 1 in 10 chance of 6-hour tallies reaching 3-4 inches. This is needed rain, but it may fall too quickly, sparking minor flooding, especially over urban locations. Areal averages will be lower, generally 1/2" to 1 1/2".

Highs today will be warm again, in the mid-80s, before the storms get going. Quieter conditions resume overnight, but it will remain quite balmy.

Monday...

One more day to watch the radar closely for strong storm development. As the cold front moves into Central Florida during the afternoon, the environment appears conducive for more organized bands of showers and storms, some of which may be strong to severe. AI/ML probabilities for severe hazards range from 5-15%. Primary hazards remain gusty winds of 50-60 mph, coin- size hail, and frequent lightning. More unidirectional wind profiles should limit the overall tornado threat to low/very low, but it is non-zero. This broken line of storms will likely reach the Orlando area in the early to mid afternoon before drifting toward the Treasure Coast by sunset.

Expect a breezy and warm day ahead of the front, with low to mid 80s. A few wind gusts to 30 mph can be anticipated even outside of any storms.

Remainder of Next Week...

Once the front gets south of here Monday night, cooler air rushes in. Quite a temperature gradient by daybreak on Tuesday, with 50s along the Treasure and immediate Space Coasts and 40s elsewhere. There is a 20-30% chance of reaching the upper 30s over northern Lake and Volusia counties. Wind chills are likely to dip into the mid-upper 30s northwest of I-4. High temps on Tuesday will struggle to reach the low 60s from Orlando northward, with mid-upper 60s farther south. Aside from a lingering shower along the Treasure Coast, Tuesday should be dry.

Similarly, cold temperatures are forecast on Wednesday morning over our northern communities. Winds turn onshore beginning Wednesday, beginning some modest warming (upper 60s-low 70s). This begins a timeframe of lower confidence, with the nearby trough potentially sparking bands of rain over the southern peninsula. Just how far north the rain gets is in question, but at the very least, we should see quite a bit of cloudiness. We currently have 20-40% rain chances on Wednesday from Melbourne southward, expanding to areas south of I-4 on Thursday.

The area of unsettled weather to our south should begin to move seaward beginning Friday, leaving only low shower chances along the immediate coast. Seasonably mild high temps on Friday should warm into the weekend, as probabilities for high temps of 80 deg F + reach 60-80% by that time.

MARINE

Issued at 203 AM EDT Sun Mar 15 2026

A strong cold front will approach the waters, arriving late on Monday. Ahead of it, winds turn southerly today, then freshen out of the southwest on Monday. Offshore-moving showers and gusty storms are forecast for the next two afternoons. Boating conditions will become poor to hazardous early in the work week. Behind the front, strong northwest breezes will affect the waters Monday night and early Tuesday. High pressure then drifts over the Mid-Atlantic by mid-week as the front stalls over the southern Bahamas.

Seas 3-5 ft through Monday, increasing to 3-6 ft nearshore and 7-9 ft in the Gulf Stream by Tuesday morning. Seas slowly subside by late Wednesday to 3-6 ft. Depending on the position of a surface trough near South Florida late next week, seas may become hazardous again by next Thursday and Friday.

AVIATION

(12Z TAFs) Issued at 640 AM EDT Sun Mar 15 2026

Patchy IFR/LIFR CIGs and patchy fog across interior terminals will return to VFR by 14Z or so. After a quiet morning convectively, a high coverage of SHRA/TSRA will develop during the afternoon and persist into early eve. With no capping inversion, convection may develop early and focus/initiate along sea breeze near the coast so have started with VCSH SUA-MLB at 14Z. All sites have TEMPO TSRA focused btwn 20Z-24Z with a wind gust. Lingering SHRA/TSRA past 00Z esp northern terminals. Perhaps a prevailing -RA VCTS could be warranted in the evening. All convection should diminish by midnight. Winds will have a southeast to south component today, becoming breezy behind the sea breeze at coastal terminals gusting up to 22 knots.

FIRE WEATHER

Issued at 203 AM EDT Sun Mar 15 2026

There are no fire weather concerns through Monday, but lightning storms are forecast over the district which may cause new fire starts. Over the next two days, wetting rains are expected over much of Central Florida from these scattered storms.

A cold front settles south of the area on Tuesday, delivering drier air to northern portions of Central Florida. Minimum RH values from 30-40% are forecast from near Orlando and points northward. North winds from 8-12 mph will make for fire-sensitive conditions. RH readings should increase modestly beginning Wednesday as winds turn back onshore.

PRELIMINARY POINT TEMPS/POPS

DAB 84 65 83 45 / 70 50 80 30 MCO 85 67 83 48 / 90 50 80 30 MLB 82 66 84 51 / 80 60 80 50 VRB 83 66 85 54 / 70 60 80 50 LEE 85 66 81 45 / 80 50 80 20 SFB 86 66 83 47 / 80 50 80 30 ORL 85 67 83 48 / 90 50 80 30 FPR 83 65 86 53 / 70 60 80 50

MLB WATCHES/WARNINGS/ADVISORIES

FL...None. AM...Small Craft Advisory from 8 AM Monday to 10 PM EDT Tuesday for AMZ570-572-575.