Sunrise 6:01 AM   Sunset 7:45 PM Moonrise 3:38 PM   Moonset 4:33 AM

  Print   HELP   Reset   Save   Recall

LMZ543 Expires:202404200200;;021044 Fzus53 Kgrb 191601 Nshgrb
nearshore marine forecast national weather service green bay wi 1101 am cdt Fri apr 19 2024
for waters within five nautical miles of the shore on lake michigan
lmz542-543-200200- sturgeon bay to two rivers wi-two rivers to sheboygan wi- 1101 am cdt Fri apr 19 2024
.small craft advisory in effect until 7 pm cdt this evening - .
This afternoon - W wind 15 to 25 kts with gusts to around 30 kts. Mostly cloudy. Waves 2 to 4 ft subsiding to 1 to 3 ft late. Tonight - W wind 10 to 20 kts with a few gusts to around 25 kts. A chance of sprinkles and flurries after midnight. Waves 1 to 3 ft. A small craft advisory may be needed. Saturday - W wind 10 to 20 kts with gusts to around 25 kts. A chance of flurries in the morning. A chance of sprinkles. Waves 2 ft or less. Saturday night - W wind 5 to 10 kts increasing to 10 to 20 kts after midnight. Clear. Waves 2 ft or less.

LMZ500
No data

FXUS63 KGRB 191143 AFDGRB

Area Forecast Discussion National Weather Service Green Bay WI 643 AM CDT Fri Apr 19 2024

Updated aviation portion for 12Z TAF issuance

KEY MESSAGES

- Gusty west winds of 30 to 40 mph over central to northeast Wisconsin will create conditions hazardous to small craft and may blow loose objects around today.

- Elevated fire weather conditions are possible on Sunday and Monday afternoon due to low relative humidities ranging from 25 to 30 percent and sustained winds of 10 to 20 mph.

- Next chance for precip returns late Monday through late Tuesday.
Rain appears to be the main precipitation type, but some snow may mix in across the far north on Tuesday.

DISCUSSION
Issued at 417 AM CDT Fri Apr 19 2024

Short Term
Today
Tonight...and Saturday

A vigorous mid level shortwave will track through northern Wisconsin today around the periphery of a broad mid level low situated across western Ontario. This shortwave will take advantage of steep low level lapse rates of 8 to 10 C/km all the way up to around 750 mb. This will produce some convectively induced showers (20-30 percent chance) west and north of the Fox Valley today with a bit deeper moisture. The Snow Squall Parameter indicates there will be the potential for a snow squall across north-central Wisconsin as this value hovers around 1.
Although snowfall amounts on roadways are expected to be de minimis given the sun angle this time of year, some light accumulation on grassy surfaces cannot be ruled out. Further south, moisture will be limited across east-central Wisconsin with a sprinkle possible.

Winds at the top of the boundary layer will be fairly high today around 40 knots, with westerly winds gusting to 30 to 40 mph at times at the surface given the deep boundary layer and steep low level lapse rates. The highest winds will be across central and east- central Wisconsin with higher winds in the boundary layer, with slightly lower wind speeds across north-central Wisconsin.

Highs today are expected to range from the lower 40s across the north (with temperatures likely falling into the mid to upper 30s once the showers begin), to around 50 across east- central Wisconsin.

Light snow showers or flurries could continue tonight across north-central Wisconsin as an additional shortwave and mid level trough swing through the western Great Lakes region. Again some light accumulation is possible tonight on grassy surfaces, with some roadways possibly seeing accumulations after sunset. Lows tonight are expected to range from the middle 20s across the north, with lows in the lower 30s across east-central Wisconsin.

Cyclonic flow flow will remain across the western Great Lakes region on Saturday as a weak mid level shortwave tracks through Wisconsin. Steep low level lapse rates of 8 to 10 C/km will remain, although only to around 800 mb. Some models are suggesting another round of showers on Saturday with this shortwave while others remain dry with less moisture available. Given some models are signaling precipitation and the presence of a mid level shortwave will introduce a small chance (10-20 percent) of some light rain/snow showers or sprinkles/flurries on Saturday. Highs on Saturday are expected to range from the middle 40s across the north, with around 50 expected across east-central Wisconsin.

Long Term...Saturday Night Through Thursday

Dry conditions are anticipated for the remainder of the weekend and through much of Monday as high pressure resides over the area.
The high pressure will gradually exit on Monday and make way for the next chance for precip Monday night through Tuesday night as a surface low pressure system and cold front move across the region. Timing and placement of the low still have a large spread, in addition to differences in the strength of the upper- level shortwave/trough. Southwest flow on Monday will lift warmer air into the region, resulting in rain at the onset of this precip.
There is still some potential for a mix of rain and snow across the far north on Tuesday, but this will depend on the track of the surface low. If the low tracks across the central part of the state, there will be a higher chance for a mix of rain and snow across the north, but if the low tracks across Upper MI like some guidance is indicating, only rain would occur. Models with the latter solution also show steep enough mid-level lapse rates that a few embedded thunderstorms could occur. Dry conditions return for midweek following this system as high pressure and ridging build into the area.

AVIATION
for 12Z TAF Issuance Issued at 643 AM CDT Fri Apr 19 2024

Partly to mostly clear skies will become mostly cloudy throughout the morning with daytime heating with SCT-BKN VFR clouds expected through the afternoon/evening. Isolated to scattered snow showers are expected late this morning and afternoon, especially north of and west of the Fox Valley. Expecting mainly VFR conditions, with MVFR ceilings/visibilities possible, especially at RHI and AUW/CWA. Low level instability could produce some brief heavier snow showers. The snow shower activity will decrease in the evening across much of the area, but could linger across north- central Wisconsin.

Surface winds will increase today and remain gusty this afternoon with west winds gusting to 25-35 knots. Winds will slacken off a bit tonight, with gusts of 10-20 knots expected.

FIRE WEATHER
Issued at 417 AM CDT Fri Apr 19 2024

Confidence is increasing for elevated fire weather conditions Sunday and Monday, as a dry airmass prevails. Afternoon RH values will fall into the 25 to 30 percent range on Sunday and into the 25 to 35 percent range on Monday. Winds look to be a little higher on Sunday, with sustained winds of 15 to 20 mph and gusts up to 30 mph. Sustained winds on Monday to be between 10 to 15 mph, with gusts up to 25 mph. Not anticipating meeting red flag warning criteria as temperatures will be below the threshold in the mid 50s to low 60s each day. Will continue to message the elevated fire weather conditions in the HWO.

GRB WATCHES/WARNINGS/ADVISORIES
None.

toggle option: (graph/table)

Full Color Weather Map

Link to Loop


Other links: GEOS-West     Contential US     Full GOES-East

Green Bay, WI,