July 6: Strong Storms Today, Daily Links

WEATHER

The possibility of severe thunderstorms this afternoon is occupying most of our attention today, but before the storms develop we’re going to be dealing with plenty of heat and humidity.  High temperatures will reach the low 90s this afternoon:
WEDNESDAY HIGHS
With dew points still in the low to mid 70s:
WEDNESDAY DEW POINTS
MuggyMeter
That means the heat index will max out in the upper 90s to around 100 degrees (I think Futurecast is a little too toasty, but these numbers are certainly in the realm of possibility):
WEDNESDAY HEAT INDEX
In a word, gross.

The heat and humidity will be the fuel for some strong thunderstorms this afternoon and this evening.  The forecast models are depicting slightly different scenarios regarding storm development, strength and timing…the RPM model shows spotty storms popping up by noon, with scattered strong storms coming at us in waves — one round of storms by mid-afternoon, another this evening, and still more strong storms late this evening and overnight:
RPM 12P WED RPM 2P WED RPM 4P WED RPM 6P WED RPM 8P WED RPM 10P WED RPM 12A THU RPM 2A THU RPM 4A THU RPM 6A THU
The HRRR model keeps a lid on the early-afternoon activity, but brings a line of strong thunderstorms through the Midstate late this afternoon and early this evening, with another line heading in after sunset:
hrrr_2016070611_ref_nashville
As always though, no model is perfect.

Any thunderstorm that develops today will have the potential to become severe — the main severe weather threat will be damaging straight-line winds (from “wet microbursts” producing 60+mph gusts).  ANY storm, regardless of severity, will produce a lot of cloud-to-ground lightning and some locally heavy rainfall:
PAUL SEVERE RISK GRAPH - LIGHTNING
There isn’t enough wind shear in the atmosphere overhead to make tornadoes a cause for concern, and the depth of the hot air in the atmosphere should be sufficient to melt any large hail before it reaches the ground.

This morning, the Storm Prediction Center initially outlined a “Marginal Risk” (level 1 of 5) for severe thunderstorms, only along and north of the TN/KY state line.  I didn’t buy that, and apparently neither did the next shift of SPC forecasters, because their 8am outlook significantly expanded the Marginal Risk and “Slight Risk” (level 2 of 5) regions:
PAUL SEVERE RISK REGION
That’s a lot closer to my line of thinking, but I think the Slight Risk will eventually end up around I-40 — the SPC’s own forecast model (the short-range ensemble forecast) shows a 40-50% chance of thunderstorms with severe characteristics this afternoon:
SREF_prob_combined_supercell__f015

The best chance of spotty storms on Thursday looks to develop to the north and northeast of Nashville, but we’ll keep a close eye out for changes — today’s storms could re-arrange the environment a bit and mess things up:
RPM 3P THU RPM 6P THU

With drier weather for the rest of the Midstate on Thursday, temperatures will be able to climb up to the mid 90s…
THURSDAY HIGHS
…with heat indices topping 100 degrees:
THURSDAY HEAT INDEX

There are some day-to-day differences in the 7-day forecast, but the overall theme is the same through early next week: it will be hot, it will be muggy, and scattered storms will be possible every afternoon.
WSMV 7 Day AM

 

LINKS

Nerdiness a-plenty today…links will be posted by 9am.

Advertisements

About paulheggen33

Morning meteorologist for WNCN-TV in Raleigh.
This entry was posted in Uncategorized and tagged , . Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s