We are now on day 18 without any significant rain in the Otsego/Plainwell area. Yesterday we had a high of 86° and the low was 59°. The SPC outlook has had the slight risk level 2 area creep into western Michigan. Thunderstorms are expected to develop in portions of Lower Michigan, most likely in west/southwestern areas, late today. Light rain could precede thunderstorms during the evening in West Michigan. The farther east you are, the better your chance of outdoor activities staying dry during the evening. Thunderstorms during the night could drop a lot of rain in a short amount of time, with a chance of a few locations seeing large hail or damaging wind gusts.
Here is the current SPC Outlook for this evening and overnight, into Tuesday.
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SPC Convective Outlook Day One
Early this morning, satellite imagery suggests two distinct short-wave troughs are progressing through the upper ridge across the northern/central Plains region. Each of these features will likely contribute to scattered robust convection that should spread across the upper Midwest into the Great Lakes region. Multiple thunderstorm clusters are ongoing across the Dakotas into eastern NE at 0530z. This activity will propagate into MN/IA early in the period as LLJ is drawn into this region in response to the progressive short waves. Flattening height field across MN/WI, and a strengthening LLJ across the Great Lakes during the latter half of the period, suggest multiple warm-advection thunderstorm clusters should advance downstream as air mass recovery contributes to buoyancy for robust updrafts. While deep-layer flow/shear would seemingly support supercell structures, storm mode will likely be larger clusters with the possibility for one or more MCSs. Damaging wind/hail are the primary threats if this scenario does unfold.
SPC Convective Outlook Day Two
A complex and messy forecast scenario is apparent across these regions on Tuesday. A loosely organized cluster of thunderstorms may be ongoing at the start of the period Tuesday morning across parts of the Midwest/Ohio Valley. This activity should be associated with a weak mid-level shortwave trough that is forecast to progress eastward across the OH Valley into the Mid-Atlantic through the day. It remains unclear whether the morning convection will restrengthen as it crosses the Appalachians and reaches the coastal Mid-Atlantic by late Tuesday afternoon. Regardless, most guidance suggests that moderate instability will develop downstream through the day as diurnal heating occurs and low-level moisture returns northward. Enhanced mid-level flow should also be present to foster around 30-40+ kt of deep-layer shear, which will support organized updrafts. Any convection that can develop in this regime will have the potential to become severe and pose a threat for both damaging winds and hail. Confidence remains fairly low in the details of convective evolution and placement through Tuesday night. Still, some guidance shows one or more bowing clusters strengthening across parts of MD/VA by late Tuesday afternoon. Convective potential in the wake of the morning thunderstorms across the OH Valley also remains unclear. Regardless, moderate to strong instability should develop along/south of a front across Lower MI and vicinity by peak afternoon heating. If robust convection can develop across this region, it would pose a threat for mainly damaging winds and large hail. Some guidance suggests a threat for one or more bowing clusters across the OH Valley Tuesday evening/night. Have accordingly expanded the Slight Risk for hail/wind to encompass more of the OH Valley into southern Lower MI.
Forecast Discussion
Temperatures for Independence Day could be the warmest of the
week, reaching the upper 80s to around 90 away from Lake Michigan.
Dew points should be a little higher than Sunday, but still not
overly muggy in the lower 60s.
Ongoing thunderstorm complexes to our west originating in the
Dakotas/Nebraska will approach Lower Michigan late this afternoon.
Limited instability and a fair amount of dry low-level air will
be present, so a weakening trend is expected. There will be an
increase in high-altitude cloud cover during the day at least.
Whether the mid-level showers in the evening will be heavy enough
to disrupt outdoor activities remains a difficult question to
answer, though most of the HREF members suggest a majority of
locations will be fine with perhaps only virga or sprinkles,
especially those farther east.
There is medium and increasing confidence of thunderstorm
redevelopment occurring late in the evening/overnight along the
nose of a strengthening low-level jet, providing moisture
transport convergence beneath cooling mid levels, yielding
increasing instability late in the game. However, exactly where
within the envelope of Wisconsin/Illinois/Lake Michigan/Lower
Michigan this development occurs is quite low confidence.
Convection once established should move southeast over time.
There is a signal for a swath of heavy rainfall amounts of one-
two inches or greater in a portion of West Michigan. Isolated
large hail or damaging winds cannot be ruled out, depending on the
degree of instability present, convective mode, and orientation
of any linear system relative to the vertical wind shear. A
cooling surface layer should diminish but not completely eliminate
the potential for tornadoes, which is good since some models show
substantial 0-1 km shear and elongated, clockwise-curved
hodographs in the 0-3 km layer in the vicinity of the warm front.
-- Tuesday --
In the wake of early morning storms, Tuesday should be just a
little cooler than Monday but still warm especially in the south,
and probably borderline muggy with dew points in the upper 60s or
lower 70s.
Depending on the south/southwestward extent of convective
overturning that occurs Tuesday morning, steep mid-level lapse
rates and cooler upper-level temperatures may advect into
southern Michigan, and with the warm and moist low levels, may
contribute to MLCAPE exceeding 2000 to 3000 J/kg during the late
afternoon, though with moderate CINH. Some members of the HREF
keep this higher CAPE environment south of Michigan, so confidence
in severe weather Tuesday evening is low at this time. However, if
convection can develop in southern Michigan during the evening
(despite nebulous forcing) amid a potential high-CAPE
environment, isolated severe weather would result.
-- Rest of the week --
Mid summer ring-of-fire pattern in the northern US, on the
northern periphery of a subtropical high, will continue for
several days. Later in the week, increasing ridging in the
northern Plains and troughing in eastern Canada/northeast US will
trend our upper-level flow more northwesterly, with a tendency for
increasing surface high pressure and backdoor cold fronts.
Southwest of Michigan will see a better chance of repeating waves
of convection midweek, though ensembles point to one more chance
of storms in southwest portions of the state between Wed and Thu.
Let’s see some moderate to heavy rain! It looks spotty right now but hopefully we get hammered!
Fireworks and bands last night. Book sale early this morning, parade, breakfast, car show, yard games with the family, NY Strips for dinner, then, more fireworks tonight. Checking all the boxes this year 😉 Hope everyone is making the most of it.
Hit 90 at my house now for the 5th time this summer. It’s been a fantastic summer so far! The beginning started off pretty cool but things sure turned around!
Happy birthday, America!!
Taking a lunch break. Another great day at the lake.
“the ECMWF Ensemble (ECE) mean
forecast of precipitable water jumps to near 2.2 inches. It is unusual for the ECE to forecast values like this – it
s a once in 10 year event according to the models climatology (also known as M-Climate).”That’s the 2nd time recently that they’ve said once in a 10 year event.
I saw that as well and thought it was interesting. Although the last time they said that the last event wasn’t all that impressive except for far SW MI.
“Upscale evolution of afternoon
convection into a wind-dominant MCS is possible this evening into
tonight across portions of WI, Lake Michigan and Lower MI. If
confidence increases in a more-specific track and timing for such a
complex, a mesoscale concentration of greater probabilities may be
needed in a future outlook update.”
“warm/moist advection may support surface-based effective-
inflow parcels and a residual well-mixed boundary layer well into
southern Lower MI tonight, supporting damaging to severe gust
potential with any complex after crossing the lake.”
Happy 4th!
The SPC has just placed all of West MI in the Slight Risk area for severe weather.
I agree with SS, that, despite all our country’s flaws and current strife, I am grateful for our freedoms and opportunities and principles upon which this country was founded. On the weather note, I would love to see a good rain tonight, but it doesn’t come in a deluge, and hope the hail doesn’t materialize and wipe out our garden… :<)
Bernie… I agree with ya… A little rain at a time…
We went blueberry picking and I made raspberry jam from our backyard berries!! I am red and blue… Lol!!
Happy 4th of July! We have now reached aphelion and will now start moving closer to the sun. Yesterday the official H/L at Grand Rapids was 88/59 there was once again no rain fall. There was 95% of possible sunshine. The overnight low in MBY was 65 at the current time it is clear and 67. For today the average H/L remains at 83/62 the record high of 100 was set in 1897 and 1911. A high of 99 was recorded in 2012. The low for the date is 45 in 1972 the coolest maximum for any July 4th is… Read more »
I would love to have some rain!!
Thanks to all of those from our past and our present who have fought to keep our country free and their families who have supported them and have lost loved ones. Happy 4th!!! Stay safe!!
The military Rocks!
Bring on the rain! I hope we get pounded about 10 pm tonight!