Marine Weather and Tide Forecast for Lake City, MN

DISCUSSION
Issued at 205 PM CDT Fri Apr 25 2025

Today through Saturday... There will be a brief hiatus from precipitation through Saturday evening. Temperatures have warmed into the 50s & 60s as this morning's precipitation exits downstream into the Great Lakes. Skies have cleared out behind the system but fair weather Cu have developed. Lows will cool into the upper 30s & lower 40s. High pressure will settle in over the Upper Midwest and will support a 36 hour period of dry & seasonable Spring weather.
High temperatures will be in the 50s and 60s again on Saturday. The surface high pressure will shift eastward by Saturday night. This will allow for southerly return flow to set up across the Plains & Midwest.

Sunday & Monday... Showers & thunderstorms will develop Saturday night into Sunday morning as moisture advection ramps up behind the sfc high. These storms will not be severe, but one can expect a few rumbles of thunder and brief bursts of heavier rain. We'll dry out Sunday afternoon with isolated showers still present. High temperatures will warm into the 60s with lower 70s possible in W MN.
A potent Spring low pressure will move into the Midwest by Monday.
This will increase the low level flow ahead of the low pressure Sunday night. The increase in the LLJ will lead to the development of additional thunderstorms late Sunday night into early Monday morning. Forecast soundings would suggest these storms will have a favorable environment to work with. Favorable effective shear 35+ kts and 7.5 to 8.5C/km lapse rates will be more than enough for these elevated thunderstorms to become severe & produce isolated instances of large hail. Some of these thunderstorms will likely become severe capable of producing large hail. Wind & tornado concerns are low given these thunderstorms remain elevated.

Monday morning will see ongoing convection across portions of central Minnesota into western Wisconsin. These storms likely remain strong to severe with hail being the primary threat. Our 990-ish mb low pressure will continue to move northeast from S DAK into central MN by Monday afternoon. Stronger low level flow will allow any ongoing convection to exit the area by lunch time Monday. This morning convection may play a pivotal role in the second round of severe thunderstorms Monday afternoon & evening. Aloft, the trough remains slightly positively tilted with SWerly flow. This isn't a perfect scenario for severe weather outbreak but the atmosphere rarely produces a generic textbook set up. The morning convection should do two things: 1) Keep the flow more southeasterly ahead in the warm sector & 2) cool the mid-levels & moisten the low levels in advance of the sfc low. The finer details will wait to be ironed out later this weekend. There should be a few hour period between late Monday morning and mid-afternoon where we'll dry out - allowing the atmosphere to recover. That being said, guidance depicts a favorable environment for numerous instances of severe weather. This will not be one of those mid-Summer events where "if we break the cap it'll be bad" days that rarely produce. Recovery will occur given the impressive low level & mid level flow. There will be 35 to 45kts + of effective bulk shear, 1000 to 2000+ J/kg surface instability, 8.0+ C/km lapse rates, and favorable jet dynamics aloft. So we're going to have thunderstorms that will likely be severe - the question will be how many storms develop & what storm mode will prevail? Initial storms will likely be discrete or semi-discrete super cellular before gradually merging into an MCS Monday evening/night. So all severe hazards will be possible. Storms will exit MN by sunset & western WI Monday night.

There has been great discussion on the operations floor with what the failure modes are. Previous events (analogs) highlight some bigger historical events. This region's higher end severe weather outbreaks typically occur this time of year when we're not overwhelmed with too much instability during our peak severe season in early to mid Summer. This isn't the perfect scenario but it's one that will be able to produce severe. Please continue to monitor the forecast for the latest updates. Its never too early to plan ahead for the rounds of potential severe thunderstorms Monday morning & afternoon/evening.

Tuesday through Friday... Westerly to northwesterly flow aloft will usher in a much needed stretch of quiet weather to end April & start May. Temperatures will be seasonable, in the 60s, with few additional chance for precipitation after Monday night. The exception is a weak disturbance Wednesday night that may bring isolated showers.

AVIATION /00Z TAFS THROUGH 00Z SUNDAY/
Issued at 640 PM CDT Fri Apr 25 2025

Quiet weather this period with dry high pressure moving through the region. Cu field will be gone by 3z, with our current NNE winds becoming light and variable as well tonight. Saturday, we'll see increasing mid-level clouds and southeast winds in the afternoon as the high moves into the Great Lakes and low pressure develops on the northern high Plains.

KMSP...VFR weather conditions this period.

/OUTLOOK FOR KMSP/ SUN...VFR. Chc -SHRA/MVFR in mrng. TSRA likely overnight.
Wind S 10-15G25kts.
MON...RA/TSRA with MVFR-IFR likely in mrng. TSRA likely in aftn.
Wind S 15-20G30kts.
TUE.. MVFR cigs chc -SHRA in mrng then VFR. Wind NW 10-15G25kts.

MPX WATCHES/WARNINGS/ADVISORIES
MN...None.
WI...None.