National Weather Service Melbourne FL
1013am EDT Monday July 1 2024
Issued at 1010am EDT Monday July 1 2024
Surface analysis shows Atlantic ridge axis extends westward across central FL producing a light south flow this morning. A SE sea breeze will develop and push slowly inland. GOES-16 precipitation water product combined with the early morning radiosonde data from XMR and TBW show that noticeably drier air has moved in the mid and upper levels. This will lead to a much later lower coverage of storms today compared to yesterday. There remains higher moisture across southern sections so the inland moving sea breeze should spark scattered showers/storms over Martin/St Lucie this aftn after collision with the Lake Okeechobee breeze. There is an outflow boundary lifting NW across the Treasure coast/Lake O region from earlier convection offshore S FL. This boundary could spark isolated showers and storms into early afternoon but this boundary will likely lose its definition as the east coast sea breeze develops and takes over. A very late collision over the north interior should generate the best chance for rain/storms around and just after sunset.
The only update to the forecast was to lower Probability of Precipitation through early afternoon across northern sections, esp Lake and Volusia counties. No significant changes to winds or temps.
.PREVIOUS Issued at 311am EDT Monday July 1 2024
KEY MESSAGES:
- Increasingly hot this week, peaking by the weekend when the heat index could approach 104 to 109 degrees. Residents and visitors should consider steps to stay cool during outdoor plans for Independence Day through the weekend.
- Scattered showers and storms are forecast each day. The highest chances for storms (50-70%) will concentrate over the interior and Greater Orlando area, with lesser coverage along the coast.
- Major Hurricane Beryl is approaching the Caribbean this morning as the tropics remain unusually active for early July. Beryl, and its impacts, are still forecast to stay well south of Florida.
---------Synoptic Overview----------
This evening's upper-air analysis revealed a nearly 600 dam H5 ridge near Dallas, TX. Above-normal heigheights extend across the entire Sunday Belt and into the W Atlantic. A shortwave trough over the eastern Great Lakes will push a cold front into the Deep South this afternoon. It will undergo frontolysis before reaching Florida. A longwave trough near Idaho will work eastward over the next 48 HR, pushing the upper high closer to Florida by midweek. Ensemble guidance suggests this upper high will stall near North Florida through next weekend. This is forecast to protect Florida from any impacts from Hurricane Beryl, which will be forced WNW through the Caribbean Sea.
The near-surface ridge axis will be shunted slightly southward today as the aforementioned front approaches the state. The ridge axis will slowly return northward by the mid and late week before again nudging closer to South Florida late next weekend. Near-to-above- normal PWATs, at times exceeding 2", are forecast through much of the period. 0-3 KM mixing ratios will also hold steady between 12-14 g/kg, which ranges near the 90th percentile to the max moving average for early July. This indicates that rich low-level moisture will remain in place as the south/southeast flow dominates.
In all, this portends a fairly typical rainy-season pattern with daily scattered showers and storms, focusing over the interior on most afternoons. With the upper high nudging closer to Florida, temperatures will turn hotter than normal, introducing a risk of heat-related health impacts, especially for those outdoors during the upcoming Independence holiday and weekend.
-----Sensible Weather & Impacts-----
Today & Tonight... A bit of patchy ground fog is possible through 8 AM. Later on, the weakening front sagging southward, along with a batch of moisture across SoFlo, will be the foci for shower and storm coverage. This is represented well in our digital forecast, with 50-60% storm chances along the Treasure Coast as well as areas near and north of Orlando. For Daytona Beach to the Space Coast, storm chances are lower, closer to 30-40%; this could be generous. As for timing, HREF members show scattered storms popping along the Treasure Coast after 2 PM. Near Orlando and points north/west, a fairly late sea breeze collision is expected amid the background southerly flow, so it wouldn't be surprising to see storms holding off until after 4-5pm and lasting through mid-evening here.
High temperatures will respond to a bit more sunshine and later storm development, with low/mid 90s fairly common. Peak heat indices will reach 101-106F in most locations. Lows tonight will fall into the mid 70s.
Tuesday - Wednesday... The weak front to our north dissipates but leaves ample moisture over the state. As the surface ridge axis nudges northward, background flow will back toward the southeast once again. Scattered to numerous storms should develop in the afternoon and evening hours, with coverage of 40-50% near the coast and 60-70% over the interior and Greater Orlando areas. Coverage may be slightly more impressive on Tuesday compared to Wednesday as some drier air aloft tries to work in and we begin to feel additional subsidence from the upper high. Low to mid 90s will persist, and so will the sultry humidity. Expect maximum heat index readings to inch slightly higher (102-107F). Pockets of Major HeatRisk will creep into areas north of Interstate 4, indicative of unusually hot and humid conditions even for Florida, and partly driven by overnight low temperatures running 4-7F above normal.
Independence Day - Next Weekend
Heat-related impacts will drive the weather story for this timeframe, along with at least scattered (30-60%) storm chances. Our weather will continue to be dominated by the strong upper high, characterized by H5 heigheights exceeding the 95th percentile of climatology. H85 temperatures rise to around +20C. Boundary layer flow will remain southeast early in this period before subtly veering toward the south late in the weekend. This will continue to draw high humidity out of the tropics, with dew points in the mid 70s F.
Statistical guidance continues to suggest widespread mid 90s over the interior and low/mid 90s along the coast. Peak heat indices are forecast to range from 102-107F for the Fourth of July and Friday before climbing toward 104-109F next weekend. A Heat Advisory (108F) may be warranted for at least some of this timeframe as we get closer in time, especially considering the number of residents and visitors who will be spending time outdoors. Planning to enjoy our beaches, attend holiday celebrations, or visit area attractions? Make sure to pack the water and sunscreen, and expect to need some time in the shade, A/C, or pool!
Much of the troposphere will remain warmer than normal, contributing to relatively poor mid-level lapse rates. Through Saturday, the southeasterly flow should hold the higher storm chances over the interior (50-60%), with lesser coverage (30-40%) along the coast. Storm chances may creep up late in the weekend as the flow veers southerly and mid-level temperatures dip slightly.
A low pressure system in the tropical Atlantic (Invest 96L) currently has a 70% chance of development as it moves toward the Windward Islands late this week. 30/12Z grand ensemble guidance suggests that the upper high will force this disturbance on a track similar to Beryl into the Caribbean. However, this will be something to monitor over the coming days.
Marine
Issued at 311am EDT Monday July 1 2024
Today-Friday... An axis of high pressure will move from Central Florida today northward toward the Carolinas by midweek. SSE winds from 10-15 KT today will subside to around 10 KT while shifting slightly toward the SE from Tuesday through the rest of the period. The daily sea/land breeze circulation will form, locally enhancing breezes in the afternoon and turning winds light southerly or southwesterly during the overnight hours near the coast. A few showers and storms are possible, but a lot of dry time is forecast. Seas will range 2 FT or less through tomorrow, then 2-3 FT through Friday. Intracoastal and inshore boaters will notice a light to moderate chop.
NOAA Melbourne FL Office: Watches - Warnings - Advisories
FL...None. AM...None.
