Area Forecast Discussion Issued by NWS Melbourne, FL
000
FXUS62 KMLB 011854
AFDMLB
Area Forecast Discussion
National Weather Service Melbourne FL
254 PM EDT Thu Jun 1 2023
...New UPDATE, MARINE, AVIATION, HYDROLOGY, PREV DISCUSSION...
...Heavy Rainfall Threat through the End of the Week...
.DISCUSSION...
Currently-Tonight... It`s currently more active today at this
time as compared to the last few days. KMLB radar imagery shows
scattered to numerous showers and lightning storms across central
Florida, mainly across areas to the south and east of I-4. Towards
Volusia county, drier air has filtered in on the back side of
high pressure situated over the Northeastern CONUS, as well as an
area of low pressure located over the western Atlantic. Meanwhile
an area of low pressure remains located over the Gulf of Mexico
which the National Hurricane Center has now indicated has a 70%
chance of tropical development over the next 48 hours.
Scattered to numerous showers and lightning storms will continue
to develop across east central Florida into the afternoon with
persistent onshore flow in place, as well as outflow from storms
that develop over the Gulf and western Florida. The primary
hazards will be heavy rainfall with amounts up to 1-3" (isolated
spots up to 4-6"), in addition to, the potential for wind gust up
to 40-50mph, small hail, and frequent lightning strikes. Rain
chances will linger into the overnight hours with isolated showers
and storms possible, especially to the south of I-4 and towards
the coast. Overnight low temperatures will reach the upper 60s to
low 70s.
Friday... A similar pattern will remain in place tomorrow as low
pressure (potentially tropical) over the eastern Gulf of Mexico
slowly tracks south and east towards Cuba. Meanwhile, rain chances
will increase into the afternoon as outflow from upstream storms
over the Gulf interact with the west coast sea breeze, as well as
onshore easterly flow. Scattered to numerous showers and lightning
storms are forecast once again into the afternoon towards the
peak diurnal maximum. Any storms that develop will have the
potential to once again produce heavy rainfall up to 1 to 3"
(isolated 4-6"), wind gusts up to 40-50mph, small hail, and
frequent lightning strikes. Expect lower rain chances to the east
northeast of I-4, especially towards Volusia county. High
temperatures are forecast to top out in the low to upper 80s.
The Weekend (modified previous discussion)... Continued rain and
thunderstorm chances, maximized during the afternoon and evening
hours, will continue into the weekend. Models have come into
better agreement on the track of the tropical system, taking it
toward the west side of Cuba by Saturday morning as it encounters
unfavorable atmospheric conditions and quickly becomes
disorganized.
For east central Florida, we can expect more rounds of scattered
rain and isolated lightning storms Saturday, with more questions
about convective coverage on Sunday. Despite some differences in
the guidance beyond Saturday, what remains clear is that plenty of
moisture will remain in place over the area. PW of 1.7 to 1.9"
will support the potential for heavy downpours and isolated
instances of localized flooding. The Friday-Saturday QPF paints
the highest rainfall totals from Osceola County southward,
generally in the 0.50" to 1.25" range. It would not be
unreasonable to see localized totals approach the 2.00" mark,
especially closer to Lake Okeechobee and the Treasure Coast. Lower
amounts to the north, anywhere from 0.10" to 0.50", are expected
Friday through Saturday night.
Less certainty in the forecast remains for Sunday, as medium range
models indicate varying organization and strength of a 500mb trough
moving across the Florida Peninsula Sunday afternoon. Slightly more
energy depicted in the ECMWF suite provides greater coverage of
showers and thunderstorms Sunday afternoon, compared to less
organized mid level energy and lower QPF in the GFS guidance. A few
more model cycles will likely resolve this disagreement, especially
once the Gulf low and large-scale pattern across the southern and
eastern CONUS is more accurately captured.
Precipitation, associated cloud cover, and a north-northeasterly
wind will keep temperatures at bay. Highs in the low to mid 80s are
forecast Friday and Saturday, warming slightly on Sunday due to less
cloud cover.
Monday-Thursday (previous discussion)... Lower PW values advect
southward across north central Florida Monday into Tuesday,
falling to the 1.2"-1.4" range by mid to late week. While daily
afternoon rain chances remain in the forecast only 15-30 PoP was
included through the week. Quasi-zonal flow aloft keeps us in a
drier holding pattern through late week, even as a cold front
drops south across the Southeastern U.S. and an active weather
pattern takes shape over the Florida Straits and Carribean.
Daytime highs will increase by a few degrees from Monday to
Tuesday, signaling a change in the low-level flow from
northeasterly to west-southwesterly. A much warmer pattern takes
hold Tuesday through Thursday with highs reaching the low 90s.
&&
.MARINE...
Issued at 252 PM EDT Thu Jun 1 2023
Currently-Friday... Scattered to numerous showers and storms
continue to be expected, mainly in the afternoon with onshore
flow in place. East to northeast winds around 10-15kts will build
seas 2-4 feet with up to 5ft in the Gulf Stream.
Saturday-Monday (modified previous discussion)... Onshore flow
continues into the weekend, albeit becoming more northeasterly.
Flow backs to the NNE Sunday, strengthening to 10-17 kt, then
gradually decreasing into Monday and veering easterly Monday
night. Seas 2-4 ft thru Saturday, mostly 2-3 ft Sunday, then
quickly increasing in response to the stronger northerly winds
Sunday night. Seas 2-4 ft near shore and 4-6 ft offshore thru
Monday.
In addition, daily rain and lightning storm chances may create
briefly higher seas Friday thru Sunday. Rain chances begin to
decrease Monday as drier air starts to filter south across the local
waters.
&&
.AVIATION...
(18Z TAFS)
Issued at 252 PM EDT Thu Jun 1 2023
VCTS at all terminals this afternoon. TEMPOs across the interior
terminals and TIX for below VFR CIGs/VIS in convection. VCTS/VCSH
expected to diminish before 03z. ENE winds around 10-12kts. Gusts
around 20kts possible across northern terminals this afternoon.
Winds diminish to around 4kts overnight.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 71 82 70 82 / 30 30 10 40
MCO 71 85 71 86 / 20 70 20 50
MLB 73 85 72 84 / 40 50 40 50
VRB 71 86 71 85 / 40 60 40 60
LEE 70 87 69 88 / 20 60 10 40
SFB 71 86 70 87 / 20 50 20 50
ORL 72 87 71 87 / 20 60 20 50
FPR 71 83 71 83 / 50 60 50 60
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...None.
&&
$$
Fehling/Law/Haley