Daytona Beach, Florida 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

973
FXUS62 KMLB 201919
AFDMLB

Area Forecast Discussion
National Weather Service Melbourne FL
319 PM EDT Sun Jul 20 2025

...New KEY MESSAGES, DISCUSSION, MARINE...

.KEY MESSAGES...
Issued at 306 PM EDT Sun Jul 20 2025

- A Heat Advisory remains in effect until 6 PM for Lake, Orange,
  Osceola, Okeechobee, Seminole, Volusia, and Brevard counties for
  peak heat indices of 108 to 110.

- Hot and humid conditions with peak afternoon heat indices up to
  110 and Moderate to Major HeatRisk impacts continue across
  portions of east central Florida through early this week.

- Rain and lightning storm chances remain below normal through
  today, with chances increasing once again through the work week
  as a weakening front and high moisture approach from the north.

&&

.DISCUSSION...
Issued at 306 PM EDT Sun Jul 20 2025

Currently...Slightly drier conditions than yesterday, with
dewpoints coming in a few degrees lower, and also apparent in the
slower start to the cu-field this morning. A band of relatively
higher moisture, notably in the low-levels key to deep convection,
remains draped across the northern counties, where GOES satellite
imagery shows PWATs around 1.7-1.8" and a few showers developing
along lake boundaries, compared to 1.4-1.6" to the south. The
pressure gradient across the Florida peninsula has become very
weak as the ridge axis of the Atlantic high pushes into South
Florida, and while southerly flow continues to the south around
the ridge axis, some weak northerly flow has set in across the
north from a weak surface high in the northeastern Gulf.

Rest of Today-Tonight...Despite the dry conditions, there appears
to enough hope for a shower or storm across East Central Florida
this afternoon and evening to support a fairly broad low (20%)
chance in the forecast. The highest rain chances of 30-40% have
shifted south a bit into mainly Orange and Osceola counties, where
there is likely weak convergence from the northerly and southerly
flow fields, and not too far from the higher moisture (i.e. more
favorable environment for convection). Any storms that do manage
to develop may be capable of producing lightning strikes, wind
gusts to 45 mph, and brief heavy downpours. Activity is forecast
to diminish into the overnight hours, with mostly dry conditions
tonight.

Temperatures have climbed into the L-M90s, and are expected to
find another degree or two by peak heating, which combined with
the humidity, will produce heat indices up to 103-110 across East
Central Florida. A Heat Advisory remains in effect until 6 PM for
Lake, Orange, Osceola, Okeechobee, Seminole, Volusia, and
Brevard counties for peak heat indices of 108 to 110. Residents
and visitors alike are advised to remain well-hydrated, take
frequent breaks in the shade or air conditioning, dress
appropriately for the heat, and if possible, shift any outdoor
activities to cooler parts of the day. Check in on family and
neighbors who are particularly sensitive to the heat, and never
leave children or pets in cars unattended for any period of time.

Monday-Tuesday...The mid-level ridge shifts farther west into the
Gulf and eventually back into the Central US in response to a
long-wave trough over the Eastern Seaboard/West Atlantic. A
broad/weak mid-level disturbance east of the Bahamas follows the
ridge, moving gradually towards Florida. At the surface the
Atlantic high weakens, shifting the ridge axis well south of the
area. Despite the weakening of the high, the pressure gradient
actually tightens a bit as the front from a large low pressure
system pushing offshore the Northeast drops into the Southeast,
resulting in modest southwesterly flow. Moisture increases over
Florida ahead of the front, with PWATs increasing to 1.7-1.9"
(around normal) Monday, and over 2" (at or above 90th percentile
for the time of year) Tuesday. There is potential for a surface
low to develop along the front as it stalls near North Florida
Tuesday or so, but there remains a fair amount of uncertainty if,
where, when, and what direction it goes.

Heat will continue to be concern Monday as the southwesterly flow
brings afternoon temperatures in the M90s to most of East Central
Florida, including much of the coast, which combined with the
increasing moisture will continue to produce peak afternoon heat
indices up to 110 across nearly all of the area. While increasing
cloud cover Tuesday brings temperatures down a couple degrees,
afternoon highs still remain above normal and the added moisture
will keep heat indices up around 103-107, keeping conditions nasty
even if we don`t quite make it to advisory heat. With the
increased moisture and the front in the neighborhood, rain chances
increase again to 20-60% Monday and 50-70% Tuesday, highest to
the north, in the afternoons and evenings. Storms will be capable
of producing lightning strikes, gusty winds, and heavy downpours
that could lead to minor, localized flooding in some spots.

Wednesday-Saturday...Some uncertainty in the extended portion of
the forecast depending on if and how the low develops on the
front. Ensemble members offer a gambit of scenarios, with only
some developing a low, some quickly killing it, and a bimodal
distribution between the feature tracking westward across Florida
(this is the favored direction at least) and ejecting it eastward
into the Atlantic. The consensus is for the anomalously high
moisture piled up near the front along the Southeast Atlantic
Seaboard to shift westward across Florida and into the Gulf in
some form, continuing very high rain chances Wednesday and
Thursday. Drier air following the storm begins to filter in Friday
and Saturday, bringing rain chances back closer to normal.
Seasonally warm temperatures expected through midweek with the
higher rain chances and cloud cover, then temperatures forecast to
increase again late week.

&&

.MARINE...
Issued at 306 PM EDT Sun Jul 20 2025

The ridge axis of the Atlantic high shifts south of the area as a
weakening front drops into the Southeast and western Atlantic,
approaching North Florida by Tuesday. Modest southwesterly flow
develops between these two features, with winds backing to the
south-southeast in the afternoon with the sea breeze, which will
be slow to move inland and could even become pinned near the
coast. There is potential for a disturbance to develop along front
Tuesday or so, uncertainty how (or if) the feature will develop is
higher then normal, and mariners should continue to monitor the
forecast, as winds and seas could deteriorate midweek. Regardless
of development, moisture increasing ahead of the front will bring
back high chances for showers and lightning storms, especially
Tuesday through Thursday.

&&

.AVIATION...
(18Z TAFs)
Issued at 140 PM EDT Sun Jul 20 2025
Winds are light and variable today outside of the Atlantic sea
breeze circulation, which has turned winds onshore at our coastal
terminals, generally at or below 10 knots. Guidance has been
consistent with isolated to scattered convection (SHRA/TSRA)
over the interior in the vicinity of a weak surface trough.
Given recent models runs, opted for short TEMPO at KMCO/KISM
(will continue to watch surrounding terminals where VCTS is held
for now).

Much advertised surge of higher moisture expected to build down
the peninsula from north to south on Monday. Expect higher
coverage of showers and storms in the afternoon, which will be
addressed by future forecast packages.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  76  94  76  91 /  10  60  50  70
MCO  76  96  76  93 /  20  50  40  70
MLB  76  94  76  91 /  10  40  40  70
VRB  74  94  74  92 /  10  30  30  60
LEE  77  94  78  91 /  10  60  40  70
SFB  77  96  77  93 /  10  50  40  70
ORL  78  96  77  93 /  10  50  40  70
FPR  73  94  74  92 /  10  30  30  60

&&

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...Heat Advisory until 6 PM EDT this evening for FLZ041-044>046-053-
     058-141-144-247-347-447-547-647-747.

AM...None.
&&

$$

DISCUSSION...Haley
AVIATION...Ulrich