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7 Day Forecast for Marine Location Near Howard, WI

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Area Discussion for - Green Bay, WI

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FXUS63 KGRB 071119 AFDGRB

Area Forecast Discussion National Weather Service Green Bay WI 619 AM CDT Fri Aug 7 2020

Updated aviation portion for 12Z TAF issuance

SHORT TERM. Today . Tonight . and Saturday Issued at 300 AM CDT Fri Aug 7 2020

One more fairly quiet weather day across northeast Wisconsin before the chance of showers and storms arrives tonight into Saturday. Dangerous swimming conditions will likely develop along the Lake Michigan shoreline Saturday afternoon/evening.

Today: A surface ridge, centered over lower Michigan, will drift slowly eastward throughout the day. This will keep much of northeast Wisconsin under the western edge of the ridge, allowing steadily increasing low-level moisture on southerly winds. A subtle warm front is expected to lift northward across MN and northwest WI this afternoon into early this evening. This could touch off an isolated shower or two across central WI (small chance), while the rest of the area is expected to remain dry. Continued the dry forecast as confidence in any locations seeing measurable precipitation is very low. The southerly flow will allow dewpoint to continue to increase across the area, causing it to feel a bit more uncomfortable outside. This will be in combination with steadily increasing temperatures. Dewpoints will likely remain in the low to mid 60s, with the 70 degree dewpoint building into the northern Plains. High temperatures are expected to warm into the low to mid 80s for much of the area, cooler along the lakeshore.

Tonight: The surface ridge continues to slide eastward, allowing moist southerly flow to continue to stream northward into the area during this time period. Mid/upper-level ridging is expected to be in place through the evening; however, models continue to point toward a MCS developing across the northern Plains, then shifting eastward through the overnight hours along the periphery of the ridge. Models continue to have some issues resolving exactly where this feature will trek; however, a majority of the solutions take the MCS across northern MN and then into the U.P./Lake Superior late tonight into early Saturday morning, between 06Z and 12Z. Have increased the pops across the north during that time period with scattered to widespread showers and storms. Instability is not forecast to be overly impressive with the wave arriving late in the night, in fact, most models only paint out 300-600 J/kg across central into north-central WI. Shear is only forecast to be around 20 kts as the shortwave stays north of the area, which would tend to favor a slow diminishing trend and less organization as the showers and thunderstorms approach the area. SPC has NE WI in a general thunder risk with a Marginal Risk of severe thunderstorms as close as northwest WI. Any storms that do make it into central/north- central WI will have the potential to produce heavy downpours as PWAT values are progged to be between 1.5 and 2 inches. Otherwise, overnight lows are expected to be mainly in the 60s.

Saturday: The aforementioned shortwave is expected to continue to shift eastward throughout the day, which will allow for a steady diminishing trend in any shower and thunderstorms activity. The most widespread coverage will be early in the day with the shortwave being nearby or overhead during that time period. This would be between 12Z and 18Z, slowly diminishing from the south and west. Again, heavy downpours would be the main concern. During the afternoon hours, capping in place across at least the southern part of the area should allow for a break in the shower and thunderstorm activity. Again, not expecting severe weather as shear values are expected to remain around or below 20 kts throughout the day. MUCAPE does increase during the afternoon hours, but soundings suggest that a healthy cap would have to be overcome before pop up storm could occur. At this point, have kept isolated showers/storm in the forecast, but the next shift may be able to pull this if it looks like the inversion will be strong enough to keep convection from occurring. Temperatures may be slow to increase Saturday morning with additional cloud cover; however, breaks in the clouds during the afternoon should allow most locations to warm into the low to mid 80s with dewpoints increasing to the mid to upper 60s. It will definitely feel more muggy during the day Saturday! The southerly flow across Lake Michigan will also allow waves to build along the Lake Michigan shoreline and will lead to dangerous swimming conditions Saturday afternoon. A Beach Hazard Statement will likely be needed for that time period.

LONG TERM. Saturday Night Through Thursday Issued at 300 AM CDT Fri Aug 7 2020

Zonal flow at 500mb will continue through much of the period. High temperatures Sunday should run six to nine degrees above normal, otherwise the remainder of the forecast period should remain a few to several degrees above normal.

The first piece of energy at 500mb will be east of the area by 00z Sunday. A secondary upper level disturbance will move across northern Wisconsin Saturday night, bringing a small chance of showers and storms across the north. Sunday morning should start out dry, then the chances of showers and storms increase during the day. Sunday should be the warmest day during the period with highs in the middle to upper 80s. Dewpoints are expected to rise into the upper 60s to lower 70s at most places. Still some timing differences in when the front will move across the area, but it now appears late Sunday night into Monday morning which is usually the least favorable time of day for severe weather. However, 0-6 km shear values are 25 to 35 knots so totally could not rule out a few strong or severe storms Sunday night into Monday morning. The cold front should exit the area Monday with showers and storms coming to an end. Dry conditions are expected Monday night through Tuesday night. Low chances of storms on Wednesday into Thursday, but confidence is low since the latest ECMWF run has come in dry. Comfortable dewpoints on Tuesday, but then start to slowly creep up towards the end of the week. High temperatures Monday through Thursday should run into the upper 70s to middle 80s.

AVIATION. for 12Z TAF Issuance Issued at 618 AM CDT Fri Aug 7 2020

VFR conditions are expected across much of northeast Wisconsin through late this evening as high pressure slowly drifts eastward. Some afternoon CU will likely become scattered across the area with bases around 5-8kft. Hi-Res models continue to show a thunderstorm complex moving into northern and central WI late tonight into Saturday morning. Have included VCTS at RHI/AUW/CWA around 09Z, but overall confidence continues to be low to medium in how quickly the showers/storms arrive and exact location that will be impacted. If these showers and storms make it to the eastern TAF sites, it would likely be just after the end of this TAF issuance.

GRB WATCHES/WARNINGS/ADVISORIES. NONE.

SHORT TERM . Cooley LONG TERM . Eckberg AVIATION . Cooley

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Weather Reporting Stations

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Stations	Dist	Age	Wind	Air Temp	Water Temp	Waves	Pressure	DewPt
GBWW3	5 mi	130 min	Calm G 1	61°F			1020.1 hPa
45014	24 mi	40 min	S 7.8 G 9.7	66°F			1020.6 hPa
KWNW3 - 9087069- Kewaunee, WI	33 mi	52 min	WSW 1.9 G 6	63°F			1021.4 hPa
MN4 - 9087088 - Menominee, MI	46 mi	52 min	SW 6 G 8	65°F	72°F		1021.3 hPa	57°F

Wind History for Kewaunee MET, WI

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Airport Reports

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Airport	Dist	Age	Wind kt	Visibility	Sky/Weather	Temp	DewPt	Humidity	Pressure
Green Bay, Austin Straubel International Airport, WI	6 mi	17 min	N 0	10.00 mi	Fair	64°F	57°F	81%	1021.7 hPa

Link to 5 minute data for KGRB

Wind History from GRB (wind in knots)

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Tide / Current Tables for

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Tide / Current Tables for

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Weather Map

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GEOS Local Image of    EDIT
NOTE: East coast views moved to GEOS-16. They are experimental and not well supported by NOAA so they may not be correct so be warned. This change required redoing a large amount of the GOES code. If the image you are expecting is not showing, please let me know. You may need to use the EDIT function to update your location.
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Wind Forecast for Green Bay, WI (9,2,3,4)

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Ground Weather Radar Station Green Bay, WI

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