The remarkable February warm spell has reached 14 consecutive days above normal and even more impressive seven straight days of 60-degree warmth. The spell which began last Friday has produced a week of temperature highs 20 to 25-degrees above normal!
Thursday marked the 19th 60-degree day of the month and and sets the record for the most in a February on record and the first 70° day of 2017. This is only the 12th February on record to produce a 70-degree day. Most recently last year.
The average temperature for February 2017 has now moved into second warmest all-time behind 1882, the warmest in 135 years to date. February is running an astoundingly 11.8° per day above normal!
STORMS TO END THE WEEK
A powerful spring-like storm is in formation late Thursday afternoon and promises an array of significant weather with it. As the storm intensifies winds will increase starting later tonight. We currently sit in the storms warm sector, wheres showers and thunderstorms are expected to develop. There is a chance of widely scattered showers and a few thunderstorms later tonight near also along a northbound warm front. These are not expected to be severe.
As the storm moves northeast and tracks into the lower Great Lakes Friday, stronger winds will blow and more unseasonably warm air sill overspread the state. Temperatures could break the record of 71° set in 2000 as there is expected to be many rain-free and dry hours.
Warm and more moist air which is more unstable, will support showers and thunderstorms as a fast moving cold front prepares to sweep east through the state. There are several ingredients that support a few strong and severe storms later in the day and into the evening in central Indiana. While severe storms are not a slam dunk, a powerful 100 mph jet stream is forecast to move overhead by late Friday night. Any storms that develop could pull down strong winds to the surface and produce localized damaging wind gusts.
The National Weather Service's Storm Prediction Center continues to highlight a portion of Indiana in a 'slight risk' of severe storms and within that outline a 'enhanced risk' that includes eastern Indiana and portions of Ohio. In an attempt to better narrow down the location of severe storms - the enhanced risk implies a 30% chance of a severe storm within 25 miles of any given point the in the highlighted area. It is possible a watch box will be issued Friday afternoon. Stay tuned.
The SPC SREF (Short Range Ensemble Forecast) model showing the powerful jet stream overhead and off the ensembles, the probability (previous three hours) of severe thunderstorms is still highlighting portions of Indiana. Extended dry time and the increase in unstable air will support the severe threat. CAPE, a measure of atmospheric energy is forecast to climb by late Friday and reach levels that will support a few severe storms.
What may be a hindrance is the timing. A later start time to the storms could reduced the severe threat. We will monitor the latest data. Be sure to check back and stay weather aware Friday afternoon and evening.
COLD BLAST COMING
After the passage of the cold front later Friday temperature are going to dive! Strong west-northwest winds will whip through the stat through early Saturday along with developing snow showers. When you waking up Saturday morning it will feel and possibly look a lot more like February! Temperatures will remain steady in the 30s Saturday afternoon with wind chills in the teens. Occasional snow flurries are likely along with a brief, passing snow shower.