Alert archive / Florida / Dense Fog Advisories in 2021

Dense Fog Advisory 9, NWS Melbourne, FL

December 3, 2021Lake County, Florida

NWS Melbourne, FL issued this dense fog advisory at Dec 3, 2021, 2:03 AM EST for Lake County, Florida. It was in force for 7 hr.

The area

The counties it named.

The facts

Issued
Dec 3, 2021, 2:03 AM EST (07:03 UTC)
Expired
Dec 3, 2021, 9:00 AM EST
In force
7 hr
Issued by
NWS Melbourne, FL

County Lake County, FL

The radar

The Melbourne radar (KMLB), 126 km from the middle of the area, began a volume at 07:01 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Cape Canaveral, FL (KXMR), launched 00:00Z, 7.1 hours before the alert went out and 123 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Cape Canaveral, FL at 00:00Z on 2021-12-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Cape Canaveral, FL at 00:00Z on 2021-12-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 54 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2200 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
54 m²/s²
0-3 km storm-relative helicity
49 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

179 
WWUS72 KMLB 030703
NPWMLB

URGENT - WEATHER MESSAGE
National Weather Service Melbourne FL
203 AM EST Fri Dec 3 2021

FLZ044-144-031400-
/O.NEW.KMLB.FG.Y.0009.211203T0703Z-211203T1400Z/
Northern Lake-Southern Lake-
Including the cities of Eustis, Mount Dora, Leesburg, Tavares, 
Clermont, Mascotte, and Groveland
203 AM EST Fri Dec 3 2021

...DENSE FOG ADVISORY IN EFFECT UNTIL 9 AM EST THIS MORNING...

* WHAT...Visibility one quarter mile or less in dense fog.

* WHERE...Lake county.

* WHEN...Until 9 AM EST this morning.

* IMPACTS...Hazardous driving conditions due to low visibility.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

If driving, slow down, use your headlights, and leave plenty of
distance ahead of you.

&&

$$

Kelly

What forecasters said that day

The local office's own words before this dense fog advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Melbourne, FL wrote its last area forecast discussion before this dense fog advisory went out at Dec 2, 8:03 PM EST, 6 hours earlier.

Area forecast discussion, Dec 2, 8:03 PM EST, 6 hours before
East Central Florida Forecast Discussion
National Weather Service Melbourne FL
803 PM EST Thu Dec 2 2021

.DISCUSSION...
Currently-Tonight...Very quiet tonight with broad high pressure
slowly building over the region. Light north-northwest flow will
keep things dry and cool with lows in the upper 40s to to mid 50s.
Patchy fog will be possible overnight with the best chance along and
west-northwest of I-4 with a weak inversion.

Friday...Expect plenty of sunshine. It should be a great end to the
workweek with dry conditions persisting. Highs are forecast to reach
the mid-to-upper 70s.

Saturday-Sunday...(Modified Previous Discussion) An upper level
trough will move eastward across MS, GA, and the FL panhandle
through the weekend. At the same time, a surface high pressure
located over the Florida peninsula will slowly move eastward through
the time period. Locally, dry conditions continue with some patchy
fog possible north and west of Titusville Saturday morning, and no
mentionable rain chances the rest of the day. Sunday, there will be
a slight chance of rain across the Treasure Coast, southern Space
Coast, and the Atlantic waters. The high level clouds that were
present on Friday will linger into Saturday, producing partly sunny
skies and possibly deterring fog formation Saturday morning. The
high level clouds will then begin to clear on Sunday, producing
mostly to partly sunny skies. Winds will be light and variable on
Saturday, becoming southeast around 5-10 mph. The warming trend will
continue through the weekend. Afternoon highs will be in the mid to
upper 70s on Saturday and upper 70s to low 80s on Sunday. Overnight
lows will be low to mid 50s from I-4 northward, and upper 50s to low
60s southward on Saturday, and upper 50s to low 60s areawide on
Sunday.

&&

.AVIATION...
VFR conditions will continue through the TAF period. Winds will be
light and variable overnight, then out of the north-northwest 5-8kts
during the daytime hours. Patchy fog will be possible especially
along and west-northwest of I-4 overnight. Although, confidence
isn't high enough to include at aerodrome sites.

&&

.MARINE...
Currently-Tonight...Boating conditions will remain favorable as high
pressure continues to build over the eastern Gulf of Mexico.
Expect light winds from the north-northwest. Sig waves 1-3 ft with
up to 4ft possible over the Gulf Stream.

Friday-Monday...(Modified Previous Discussion) Surface high pressure
across the Florida peninsula and Atlantic waters through the
weekend, continuing to push further out into the Atlantic on Monday.

Favorable boating conditions through the time period. Mostly dry
conditions expected through the weekend, with a slight chance of
showers across the Atlantic waters on Sunday and Monday. Winds will
be light and erratic through Saturday before becoming southeast
around 5-10 KT on Sunday and continuing through Monday. Seas will be
2-3 ft through the weekend before seas build briefly to 3-4 ft in
the offshore waters on Monday.

&&

.FIRE WEATHER...
Dry conditions will continue through the beginning of the
weekend. Minimum RH values will be around 40 percent over much of
the interior on Friday and Saturday. Winds will become lighter
and erratic on Friday.

&&

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

&&

JP/DKW
Hazardous weather outlook, Dec 2, 5:35 AM EST, 20 hours 28 minutes before
Hazardous Weather Outlook
National Weather Service Melbourne FL
535 AM EST Thu Dec 2 2021

AMZ550-552-555-570-572-575-FLZ041-044>047-053-054-058-059-064-141-
144-147-022100-
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-Southern Brevard-Osceola-
Indian River-Okeechobee-St. Lucie-Martin-Coastal Volusia-
Southern Lake-Northern Brevard-
535 AM EST Thu Dec 2 2021

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EAST CENTRAL FLORIDA.

.DAY ONE...TODAY AND TONIGHT.

.RIP CURRENT IMPACT...
A Moderate risk of rip currents continues at the central Florida
Atlantic beaches. While rip currents will be present all day, the
threat will be highest between 9 AM and 3 PM due to tidal effects.
Swim only within sight of a lifeguard and never enter the ocean
alone.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.
The rip current threat is expected to remain Moderate through the
weekend.

.SPOTTER INFORMATION STATEMENT...
Spotter activation will not be needed today and tonight.

Kelly

Nearby

Dense Fog Advisories in Florida, 2021Every dense fog advisory in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.