The big cool down and the cicadas.

The cicadas will go into a hibernation-type mode until the temperature is above 70 degrees during the day. They are not dead yet and this is not over. By my count of it, they will start dying off in the last week of June and they should be mostly gone by July 4th.

It will be 43 degrees for tonight's low temperature. Wow! I'm sure people will appreciate this. Here is the latest from the National Weather Service:

.Forecast Update...
Issued at 923 AM EDT Sat May 29 2021

Some weak low pressure just to the south and east of central Indiana
has produced enough lift to squeeze out weak isolated showers over
portions of the region early this morning. These should begin to
dissipate over the next few hours as the surface layer dries out in
the presence of diurnal heating.

Morning lows in the low 40s surely does not feel like late May, but
nonetheless strong solar radiation will still be a significant
factor in today`s high temperatures as clouds become mainly
scattered late this morning into the afternoon. For most of central
Indiana, the unimpeded diurnal heating should create a near dry
adiabatic PBL leading to surface temperatures in the mid 60s.
Portions of SE/E central Indiana will see slightly cooler high
temperatures as clouds fail to dissipate in time for efficient
heating.

&&

.Short Term...(Today through Sunday)
Issued at 316 AM EDT Sat May 29 2021

...BELOW NORMAL TEMPERATURES THIS WEEKEND...

An elongated low is slowly moving off to the east and an amplified
upper ridge will be settling over the area behind it. This will lead
to ample cold air advection bringing colder than normal temperatures
to the region for this holiday weekend. Surface observations early
this morning show temperatures in the mid 40s across much of central
Indiana and the same can be expected again tomorrow morning. Clouds
and light rain will continue early this morning on the backside of
the low. Most of the rain is expected to end around daybreak as
surface high pressure and subsidence move in from the west, but the
rain may linger into the afternoon for eastern Indiana due to the
upper low stalling over Ohio. The distance between the trough and
ridge axis will create tighter pressure gradients aloft and breezy
conditions at the surface. Sustained winds are expected to range
from 10 to 15 kts today with gusts getting as 25 kts. As subsidence
and dry air take over, skies will quickly clear out from west to
east this afternoon to early tonight. Temperatures through the day
will max out in the 60s and clear skies tonight will allow low to
again drop to the low 40s.

Under the influence of ridging and high pressure, pleasant
conditions are expected for Sunday, although starting out pretty
chilly. It will be dry and mostly sunny during the day, and with
highs near 70 and dew points in the 40s, it will feel more like a
fall day than early summer.

&&

.Long Term...(Sunday night through Friday)
Issued at 316 AM EDT Sat May 29 2021

The long term will start out dry with high pressure and upper
ridging in control for Sunday night into Monday.

Monday night into Tuesday, an initial upper trough will bring some
weak forcing to central Indiana. Moisture isn`t great with no good
flow of moisture into the area yet. Will go with some slight chance
PoPs with low confidence.

A larger and more potent upper trough will move in for mid to late
week. Stronger 850mb flow from the southwest will bring in better
moisture as well. Thus expect better chances for rain during this
period, but there`s enough uncertainty in the specifics to keep PoPs
no higher than chance category for most locations for any one period.

Uncertainty is highest at the end of the long term, as there are
questions on whether the upper trough will be progressive or will
slow down with a development of an upper low.

Temperatures will gradually moderate through the period, reaching
near normal values by the end of the week.

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