Active Weather Pattern

We may be entering a more entertaining weather pattern today, i.e. if you are fascinated by storms, winds and hail with flashes of lightning and rumbles of thunder.  The lack of severe weather over the past few years has been frustrating for Skywarn and storm chaser participants, or a sigh of relief for most others including insurance companies.

Many bought generators for their homes several years ago (like myself) when storms were rampant in southern Michigan.  I have used mine three times in the past five years and that was only for a few hours per incidence, just like buying new snow blowers and having to use them two or three times over the past few winters.  The same doesn’t go for buying mowers with the expectation of not having the grass to grow.

We have a fast moving system of storms and rain moving through Wisconsin this morning which we may see this afternoon if it doesn’t fizzle out.  Here is a nice write up from Scott Borchardt of the Grand Rapids NWS this morning:

Let`s talk about the elephant in the room right off the bat and
admit the forecast has lower confidence than usual or to be
expected after just the first 12 hours. All eyes are on the
convective complex currently passing through central Minnesota in
association with a speed max within northwesterly flow aloft (a
regime more typical of July than May). As the morning progresses,
the complex should adopt more of a southeasterly track along the
nose of a low-level jet through central/southern Wisconsin and
eventually northeastern Illinois, perhaps firing off a new round
of activity in northern Indiana by mid-afternoon. Now it`s hard to
discern what sort of footprint the complex will have on upstream
areas given the lack of an appreciable cold pool, but it seems the
outflow from the decaying system (or any renewed development)
ought to impede the best low- level moisture and surface-based
instability from creeping into Lower Michigan this evening,
especially considering the increased mid-level debris cloud cover
that`ll pass over our area. As such, the potential for showers
and storms this afternoon is uncertain. Several deterministic
models (both convective allowing and not) also build up a strong
pressure rise/fall couplet (+/-5 mb!) with the complex this
morning which would lead to a period of gusty southwesterly winds
locally this afternoon, but such a feature seems rather unlikely
given the weak/disorganized nature to the activity.

The 00Z CAMs offer a variety of scenarios this afternoon, but our
hunch is that the strongest activity may end up across northern
Illinois and northern Indiana where the best chance for
appreciable surface-based instability will exist. Even so, the
low-level wind fields and steep mid-level lapse rates approaching
7-7.5 K/km will be more than supportive of severe weather with
the main threat of severe hail up to golf ball (1.75") size should
we manage to achieve any surface-based instability this
afternoon/evening. There remains a stubborn signal in our far
southwestern corner (so Allegan, Van Buren, and Kalamazoo
counties) having such a non- zero chance this evening, which lines
up with the maintained SPC Slight Risk. Now in the unlikely
scenario that the convective system decays before making it to
northern Illinois and we have an untapped reservoir of moisture
and instability into Lower Michigan, we`ll have ourselves a busy
evening with both severe weather and flooding possible (and the
rest of the forecast for the next 2-3 days would likely need some
big updates). As horrible as it is to say at this venture, the
best course of action is just to watch trends hour by hour to see
how this shakes out as models really struggle in these regimes.

Showers and thunderstorms are possible area wide this afternoon and evening. A few storms may become severe mainly south of a line from Holland to Kalamazoo with large hail to golf ball (1.75″) size as the main risk.  This doesn’t bode well for those of use who just planted our gardens as hail this size are rampant leaf shredders.

Additional thunderstorms are possible Friday night through Sunday, with the highest chances Saturday night and Sunday.  I anticipate that this site will be more active today through Sunday.

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Seven Day Forecast

GRAND RAPIDS WEATHER

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KALAMAZOO WEATHER

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LANSING WEATHER

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Pollen Forecast

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