N. Ind. NWS gives emergency managers “heads up” on coming storms

Winter storm banner graphicThe northern Indiana office of the National Weather Service (NWS) sent email messages today to emergency managers and the news media regarding two winter storm systems that could affect the office’s 37-county warning area (CWA) between Feb. 28 and March 4.

Storm 1: Sat. night into Sunday night

IWX CWA map
Area enclosed in red line is the county warning (forecast) area of the northern Indiana National Weather Service office. Click the map to see a larger version.

The NWS forecasts two storm systems to affect the CWA of the northern Indiana office (see map at right). The first will arrive Saturday Night into Sunday (February 28-March 1). Regarding this system, NWS meteorologists have high confidence that snow will accumulate but low confidence regarding the location of highest snowfall amounts.

Snow should fall Saturday evening through Sunday night, with the heaviest snowfall occurring Sunday afternoon and Sunday night. The NWS forecasts storm-total accumulation of up to six inches with accumulation being greater in the southern parts of the northern Indiana office’s CWA than in the northern parts.

During this storm, roads could become snow-covered and slippery, but surface temperatures should remain high enough to allow road treatments to remain effective.

Storm 2: Tue. morning into Wednesday

A second storm will reach the area early Tuesday morning and continue into Wednesday (March 3-4).

As of this afternoon, NWS forecasters have low confidence in precipitation types and duration in any location with this storm. They expect, however, the storm to begin with snow, followed by period of freezing rain, then all rain.

The potential for snow and ice accumulation is greatest Tuesday morning, with rain falling Tuesday afternoon possibly into Wednesday.

The combination of runoff from the rain, melting snow and frozen rivers could cause flooding and ice jams.

As is always the case with winter storms, forecast confidence will increase as the storm approaches. People should monitor forecasts for changes.

Significant weather impacts possible over next several days

Two separate weather systems will bring a plethora of weather types “with significant impacts possible” in northern Indiana, southern Lower Michigan and northwestern Ohio between tomorrow (Sat., Feb. 28) and Wednesday, according to an “Area Forecast Discussion” that the northern Indiana office of the National Weather Service (NWS) issued this morning.

Heavy snow, freezing rain, sleet, heavy rainfall and flooding all are possible.

NWS meteorologists expect the first weather system to bring all snow to the region late Saturday night through Sunday. That storm could bring two to four inches of snow over approximately the northern third of the northern Indiana office’s forecast area and three to six inches over the remainder of the region, according to an infographic the NWS issued this morning (below). The northern Indiana office had no immediate plans this morning to issue any advisories, watches or warnings associated with this first storm, “but certainly something will be needed eventually,” writes NWS meteorologist Sam Lashley.

NWS infographic showing Sat. through Sun. snowfall forecast
NWS infographic

Forecasters expect the second storm system to impact the region anytime from late Monday night through Tuesday night. This system could bring a mix of snow, sleet and freezing rain late Monday night and Tuesday morning, according to the “Hazardous Weather Outlook” that the NWS issued this morning. Meteorologists expect temperatures to rise above freezing Tuesday afternoon, when locally heavy rain could fall. Rivers and streams will likely still be frozen, so this heavy rain could lead to flooding of low-lying areas as well as ice jams and flooding along streams and creeks.

The track and timing of the second storm system remains uncertain, so the forecast might change. It would be wise to continue to monitor future forecasts.

Tweet responsibly during severe weather

Tornado clip art with Twitter bird logoDuring periods of severe weather, the micro-blogging service, Twitter often explodes with information. Some tweets are helpful, others are less so.

The “Virtual Operations Support Group” blog posted an excellent article last year, “How to Tweet Responsibly in Severe Weather” that every Twitter user should read before the next severe weather event happens.

Highlights include:

  • Include the Twitter handle of your local NWS office when reporting weather.
  • Include a time stamp with on any tweet about an NWS warning and any tweet that contains a severe weather report.
  • In weather reports, also include:
    • What you saw.
    • Where it happened.
    • A photo, if possible.
  • Even if you normally prohibit Twitter from knowing your location (for privacy), enable location services while tweeting about severe weather.