Flash Flood Warning 1, NWS Melbourne, FL

Area Forecast Discussion
National Weather Service Melbourne FL
1017 AM EDT Fri Sep 8 2023

...New UPDATE, MARINE, AVIATION...

.UPDATE...
Issued at 1015 AM EDT Fri Sep 8 2023

Early convection has initiated across north Florida and the
Florida west coast as a mid level low moves southward into the
state. Morning soundings show unseasonably cold air aloft, and
the 10Z XMR sounding has recorded -10.5 C at 500 mb. Moderate CAPE
and low shear profiles in combination with modeled lapse rates
between 7-8 C/km will make for strong to marginally severe pulse
storms. Areas of dry air in the mid and upper levels could allow
for brief periods of gusty winds in the strongest storms. The XMR
10Z sounding has noted a DCAPE value of 965 J/Kg, and the
environment will be supportive of wind gust up to 60 mph where the
strongest convection occurs. Uncertainty remains in the potential
for hail to fall to the surface this afternoon. Temperatures
aloft could be supportive of small to large hail, but some melting
is expected occur within the mid and lower levels of the
atmosphere. In their morning update, SPC has now included the
majority of east central Florida in a Marginal risk (1 of 5) for
severe weather today. Storms will be slow moving with rainfall
rates exceeding 2 inch/hr. WPC has included most of east central
Florida in a marginal risk (1 of 5) for excessive rainfall, with
particular emphasis on coastal counties.

00Z hi-res model guidance suggests increasing coverage of storms
after 12pm, with the greatest coverage late in the afternoon as
the east coast sea breeze moves inland. However, current
initiation of showers and storms along the west coast could signal
an earlier start than model guidance suggests. Coverage is around
70 percent for most of east central Florida this afternoon with
slightly lower PoPs (50-60%) across Martin and Coastal St. Lucie
counties. Temperatures are expected to be a little cooler than
yesterday afternoon due to rain and additional cloud cover.
Afternoon highs are forecast mostly in the low 90s.

&&

.MARINE...
Issued at 1015 AM EDT Fri Sep 8 2023

Current observations at NOAA buoy 41009 - 20 NM east of Cape
Canaveral show SSW winds around 10 kts with seas around 2 ft.
Generally SW winds will back SE around 10-12 kts this afternoon as
the east coast sea breeze develops. Seas will remain around 2-3 ft
into tonight. Scattered showers and storms will be possible this
morning with coverage becoming numerous late in the afternoon. A few
storms could become strong with wind gusts exceeding 35 kts. Locally
higher wind and seas in vicinity of storms.

&&

.AVIATION...
(12Z TAFS)
Issued at 1015 AM EDT Fri Sep 8 2023

VFR outside of convection. Numerous showers and storms expected
through the period. VCTS at 17Z for all terminals with MVFR
VIS/CIG TEMPOs from MLB northward. There has been an earlier trend
in development of convection across west Florida this morning, and
northern TAFs will be monitored for potential amendments to VCTS
and TEMPO timing. Winds generally S/SW around 8-10 kts. The east
coast sea breeze will develop backing winds E/SE as it moves
inland. Erratic and gusty winds in vicinity of convection. Showers
ending around 01Z.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  88  71  88  73 /  70  50  50  20
MCO  91  71  91  73 /  70  50  50  20
MLB  90  73  89  74 /  70  50  50  20
VRB  91  72  90  74 /  70  40  40  30
LEE  90  71  90  73 /  70  30  50  10
SFB  91  71  92  73 /  70  40  50  20
ORL  91  73  92  74 /  70  50  50  20
FPR  91  74  90  74 /  60  40  40  30

&&

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...None.
&&

SHORT TERM...Law
LONG TERM....Schaper
AVIATION...Law

Hazardous Weather Outlook
National Weather Service Melbourne FL
1119 AM EDT Fri Sep 8 2023

AMZ550-552-555-570-572-575-FLZ041-044>046-053-058-141-144-154-159-
164-247-254-259-264-347-447-547-647-747-090330-
Flagler Beach to Volusia-Brevard County Line 0-20 nm-Volusia-
Brevard County Line to Sebastian Inlet 0-20 nm-
Sebastian Inlet to Jupiter Inlet 0-20 nm-Flagler Beach to Volusia-
Brevard County Line 20-60 nm-Volusia-
Brevard County Line to Sebastian Inlet 20-60 nm-
Sebastian Inlet to Jupiter Inlet 20-60 nm-Inland Volusia-
Northern Lake-Orange-Seminole-Osceola-Okeechobee-Coastal Volusia-
Southern Lake-Coastal Indian River-Coastal Saint Lucie-
Coastal Martin-Inland Northern Brevard-Inland Indian River-
Inland Saint Lucie-Inland Martin-Mainland Northern Brevard-
Northern Brevard Barrier Islands-Inland Southern Brevard-
Mainland Southern Brevard-Southern Brevard Barrier Islands-
1119 AM EDT Fri Sep 8 2023

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EAST CENTRAL FLORIDA.

.DAY ONE...TODAY AND TONIGHT.

.THUNDERSTORM IMPACT...
A vigorous upper level disturbance will traverse the Florida
peninsula this afternoon and evening. Both east-west coast sea
breezes will march inland and provide a focus for scattered
lightning storms from early to mid afternoon. An increase in
moisture along with daytime heating, coupled with additional
mesoscale boundary collisions, will promote numerous shower and
lightning storm coverage across east central Florida by late
afternoon and into early evening. Expect the activity to
gradually wind down and push off of the coast by mid to late
evening. Storm motion will be generally toward the northeast up
to 10 mph, but stronger boundary collisions could dictate overall
motion.

Primary storm threats include frequent lightning strikes,
torrential downpours, coin-size hail, and gusty winds of 45 to 55
mph. One or two storms could produce winds locally to 60 mph. A
brief tornado cannot be ruled out in the vicinity of stronger
boundary collisions.

.FLOOD IMPACT...
Quick 2 or 3 inch downpours are possible with stronger and slower
moving storms, as well as for areas that receive multiple rounds
of storms. This will produce considerable ponding of water on
roadways and other poorly drained surfaces.

.RIP CURRENT IMPACT...
A moderate risk of numerous, strong and life-threatening rip
currents continues at all central Florida Atlantic beaches today.
While rip currents will be present all day, the risk will be
highest this morning and again this evening, due to tidal effects.
Entering the ocean remains strongly discouraged due to the
dangerous rip current conditions. Remember to heed all warnings
from the beach patrol.

.MARINE THUNDERSTORM GUST IMPACT...
Lightning storms this afternoon and evening will produce wind
gusts in excess of 35 knots, as well as frequent cloud-to-water
lightning strikes. Mariners will need to keep an eye westward
for rapidly developing and approaching showers and lightning
storms from the mainland. Gusty outflows from storms can arrive
well ahead of the precipitation.

Inland lakes are not immune from the effects of strong storms and
hazardous boating conditions can quickly develop over lakes with
gusty winds and frequent lightning. Be prepared to seek safe harbor
well before a storm approaches your area.

.WATERSPOUT IMPACT...
Marine interests should also be alert for the potential of
waterspouts this afternoon and evening.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.
There will remain at least a moderate risk of dangerous rip
currents through this weekend.

The threat for scattered lightning storms continues this weekend
as well as into early next week. Lightning strikes, gusty winds,
and torrential downpours remain the primary threats.

Building seas and long period swells from Major Hurricane Lee
over the west Atlantic are forecast to lead to deteriorating
boating conditions over the coastal waters, and increase the
threat of life-threatening rip currents and beach erosion through
all of next week.

.SPOTTER INFORMATION STATEMENT...
Spotters should monitor the weather and self activate if needed.

Law/Sedlock

Preliminary Local Storm Report
National Weather Service Melbourne FL
130 PM EDT Fri Sep 08 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0110 PM     Tstm Wnd Gst     3 S Playalinda Beach    28.61N  80.62W
09/08/2023  M40 mph          Brevard            FL   Other Federal

            USSF tower 211 measured a 35kt/40mph wind gust from the
            northwest.

&&

Event Number MLB2300591

KRF

Special Weather Statement
National Weather Service Melbourne FL
149 PM EDT Fri Sep 8 2023

FLZ053-058-154-254-259-547-647-747-081845-
Southern Brevard Barrier Islands FL-Okeechobee FL-Osceola FL-
Inland St. Lucie FL-Inland Indian River FL-Coastal Indian River FL-
Inland Southern Brevard FL-Mainland Southern Brevard FL-
149 PM EDT Fri Sep 8 2023

...Strong thunderstorms will impact portions of western St. Lucie,
Okeechobee, Indian River, southern Brevard and southeastern Osceola
Counties through 245 PM EDT...

At 149 PM EDT, Doppler radar was tracking strong thunderstorms along
a line extending from 8 miles northeast of Kenansville to 10 miles
north of Brighton Seminole Reservation. Movement was east at 20 mph.

HAZARD...Winds in excess of 40 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Palm Bay, Melbourne, Okeechobee, Fellsmere, and Malabar.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with these storms and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with these storms.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or hard-topped vehicle. Remember, when
thunder roars, go indoors!

&&

LAT...LON 2726 8100 2730 8100 2730 8102 2733 8105
      2736 8103 2739 8112 2745 8115 2749 8120
      2755 8121 2760 8114 2766 8113 2782 8121
      2785 8124 2786 8130 2792 8131 2815 8054
      2807 8051 2724 8058 2722 8097
TIME...MOT...LOC 1749Z 256DEG 16KT 2797 8089 2723 8103

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH

Schaper

Preliminary Local Storm Report
National Weather Service Melbourne FL
154 PM EDT Fri Sep 08 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0139 PM     Tstm Wnd Gst     Orlando Intl Airport    28.42N  81.32W
09/08/2023  M47 mph          Orange             FL   ASOS

            The Orlando International Airport KMCO ASOS measured a
            47mph/41kt wind gust from the northwest.

&&

Event Number MLB2300592

Leahy

Special Weather Statement
National Weather Service Melbourne FL
154 PM EDT Fri Sep 8 2023

FLZ045-053-247-347-447-547-647-747-081845-
Southern Brevard Barrier Islands FL-Osceola FL-
Northern Brevard Barrier Islands FL-Orange FL-
Mainland Northern Brevard FL-Inland Southern Brevard FL-
Mainland Southern Brevard FL-Inland Northern Brevard FL-
154 PM EDT Fri Sep 8 2023

...Strong thunderstorms will impact portions of central Brevard,
southern Orange and Osceola Counties through 245 PM EDT...

At 154 PM EDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Haulover Canal to 9 miles west of Camp
Holly Fish Camp. Movement was east at 10 mph.

HAZARD...Winds in excess of 40 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Orlando, Melbourne, Kissimmee, Titusville, and Saint Cloud.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with these storms and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with these storms.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or hard-topped vehicle. Remember, when
thunder roars, go indoors!

&&

LAT...LON 2874 8065 2860 8054 2849 8050 2844 8051
      2839 8057 2814 8054 2791 8131 2800 8139
      2800 8142 2804 8146 2806 8146 2801 8138
      2808 8135 2809 8145 2814 8146 2814 8152
      2826 8156 2826 8166 2835 8166
TIME...MOT...LOC 1754Z 262DEG 10KT 2876 8079 2808 8091

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH

Schaper

Preliminary Local Storm Report
National Weather Service Melbourne FL
155 PM EDT Fri Sep 08 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0139 PM     Tstm Wnd Gst     5 SSE Belle Isle        28.41N  81.32W
09/08/2023  M51 mph          Orange             FL   Other Federal

            The ITWS at the Orlando International Airport KMCO
            measured a 51mph/44kt wind gust from the northwest.

&&

Event Number MLB2300593

Leahy

Preliminary Local Storm Report
National Weather Service Melbourne FL
215 PM EDT Fri Sep 08 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0210 PM     Hail             3 SSW Space Coast Stadi 28.22N  80.75W
09/08/2023  M0.25 inch       Brevard            FL   NWS Employee

            Off duty NWS employee reports pea size hail on Archdale
            Street in Viera.

&&

Event Number MLB2300594

KRF