THERE ARE SOME TWEAKS TO THIS FORECAST BASED ON THE LATEST NEW DATA. THEY ALL INVOLVE TIMING & POSITIONS OF STORMS SYSTEMS & A WARM FRONT. THIS WILL HAVE SUBSTANTIAL IMPACTS ON THE OVERALL WEATHER OUTLOOK..............
We have hit our high temperatures for today at 63-68 early this morning after a few spotty showers/t'showers lastnight to this morning. I was thinking we might be able to keep some warmth of lower 60s Lafayette & southward to midday before falling, but the chill is accelerating southward & already overtaking the entire area.
The first surge of cooler air this morning came in with the cold front. Now, the lake breeze front is moving through, dropping us into the 40s & 50s with a brisk north to northwest wind.
Note how away from the lake breeze front how temperatures reach the mid 60s in north-central Ilinois & eastern Iowa this afternoon.
A few showers & some drizzle are occurring with & just behind the lake breeze front as the north winds blow over large expanse & fetch of still cold Lake Superior & Lake Michigan water.
The few showers & drizzle should taper with time this afternoon & we should begin to see the low clouds break & then clear late afternoon-evening.
We may very well hit the heart of the cold from the Lakes in the next several hours with 45-55 over the area, then rebound to 51-58 this evening.
As this process of breaking & clearing the low clouds occurs, high & mid clouds will already begin to increase from the southwest.
This will prevent us from getting quite as cold as expected overall tonight. I went for 32-38 with clear skies & light to calm wind for tonight in lastnight's outlook. I was projecting 37 for Greater Lafayette.
With some increasing cloudiness, I am opting for 35-41 instead. There may be some patches of frost, still, but mainly in the north & northeast. I am projecting 39 for Greater Lafayette.
Here is the bit of a quandary for tomorrow.
Storm system is shifting about 100 miles north & coming in faster. It looks to bring rain to southern Indiana Wednesday night-Thursday.
It is more like Wednesday-Wednesday night with some showers sneaking into our area. However, the heaviest, most widespread rainfall will stay south of us it appears, per latest data.
So, rather than mostly sunny skies, in a shift, it looks more partly to mostly cloudy with a few to some scattered showers for Wednesday, Wednesday night & early Thursday morning. I went for average coverage of rainfall at 40% with dry hours in-between any showers. Total rainfall looks to run 0.04-0.20" by Thursday morning. A few areas will only see a trace.
Highs Wednesday look to range from 70 in the far north to 61 in the far south & around 64 in Greater Lafayette.
40s still look good for Wednesday night-Thursday morning with a few showers, followed by partly to mostly cloudy skies Thursday.
A cold front may bring a few showers late Thursday evening-night (30%) after highs during the day of 67-73. 40-46 is likely behind the cold front Thursday night as skies clear.
Friday looks good with mostly sunny skies & highs of 69-76 & lows in the 40s & 50s.
Things are getting tricky Saturday with front laid up over the area.
The area looks separated into two pieces with 50s & 60s & then 70s to 80. At this moment, it looks like the front may hang up just south of Route 26. So, it may be 50s & 60s along & north of that warm front & 70s south of it.
Some showers & storms are possible with the front, especially on the cooler side of it, followed by a wave of showers & storms for everyone Saturday night as the front sags back southward. I went for 45% coverage of rainfall Saturday & 60% coverage Saturday night.
With Greater Lafayette right on the line, it may be a situation of 60 at Battle Ground & 70s at Stockwell & 70 along Veteran's Memorial. Tough call.
Let's hope the front sets up just north of the viewing area & we are all warm. However, it looks more complicated than that at the moment.
GFS model shows the viewing area cut in half by the warm front. Note the lobe in the black lines below indicating its afternoon position.
Note the much colder air with accumulating snowfall in Minnesota & Wisconsin with temperatures around 32!
You can see in the second graphic the warm front's separation of 50s & then 60s & 70s trying to overspread part of the area from the south & southwest.
So it could be a situation of snow in southern Wisconsin with 32, but some severe weatehr risk from central Illinois through Missouri with 70s.
The colors below show the severe risk area of MARGINAL to low-end SLIGHT RISK strength. At this point, there is no risk of severe weather for Saturday or Saturday for the area, but we will monitor.
With front likely being pushed back southward Saturday night, we should drop into the 40s as any rainfall departs.
Sunday is tricky because it is unclear how far back northward warm front will get. This will determine how much, if any, rainfall occurs & just how warm we get or how cool we stay.
Right now, I took somewhat of the middle road with 25% rainfall coverage, partly to mostly cloudy skies & highs 60-72 north to south.
Monday is just as tricky. With front laid near or up in the area, some scattered rainfall is possible with partly to mostly cloudy skies. It could be a situation of 30s north & 50 south Monday morning & highs Monday 58 north to 75 south.
Tough call with front so close & even straddling the area. 40 miles with the frontal position will make all the difference as winter, spring & summer duke it out for position & dominance.
There is much better consensus that the front will surge north of the entire viewing area Tuesday-Wednesday. Highs of 77-83 are likely with lows only in the 60s with pretty high humidity & strong southerly winds. The highest dew points of the year at 63-68 are possible.
Note the risk of severe weather off & on Tuesday-Friday of next week. It will be largely warm & humid with front draped north of us & several disturbance lifts through & along that front that will create lift, good shear & dynamics atop an unstable airmass to promote episodic severe weather risk.
The colors take all of the conditions for severe weather & depict the risk with a color scheme. Yellow & orange means much higher risk with risk (SLIGHT TO ENHANCED RISK), but more isolated to scattered severe risk in any green color (MARGINAL to low-end SLIGHT RISK).
This is not a Storm Prediction Center convective outlook, but rather looking at the parameters in place to try to pinpoint where the greater severe risk could develop via a computer model.
It is the reds, pinks & purples to light blue that indicate your more MODERATE- to HIGH RISK-type of severe weather.
GEFS Ensembles show the overall increase in severe risk next week, but members vary on exact placement of higher risk, which will be determined by more immediate mesoscale factors nearer to the time of onset.
Ensembles show the trend for warmth............
& frequently humid conditions.