Archive for the ‘Weather’ Category

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The anything goes mentality of weather in this area showed as temperatures were flirting with 80s last week only to get a quick shot of snow early Saturday, and now yesterday temperatures were in the low 70s now to deal with rain changing to freezing rain.

The uncertainty of the models on Sunday made the admins go with the medium peak for Wednesday but when the NWS issued advisories for Wednesday (after the 3 PM deadline to get stuff posted here because of work) the risk was upgraded to high.

The NWS has issued an Winter Weather Advisory but we expect it to be extended or modified later today:

The high risk may have been justified after this happened at the end of the evening peak on Tuesday:

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The NWS just issued a Winter Weather Advisory for this evening on this section of 270 for favorable chances of mist, freezing rain, and to an lesser extent inversion fog and snow.  While up to .10 of ice and/or 1 inch of sleet/snow mix is expected, the main issue is that it takes very little ice to potentially cause big problems, this weekend is Mardi Gras weekend, and this area is relatively hilly.   Threat forecasts are typically not run on the weekends but the medium threats for both Thursday and Friday were there in the case the systems that dumped massive amounts of snow just 200 miles to the north ended up busting projected forecasts.  There is a likelihood this one can very well bust as well – the storm tracking just 20 or 30 miles to the south or north can make a big impact to what happens here.  Naturally I would prefer to wait until 4 to 6 hours out to make a post but I have to be at work later this afternoon and I usually go to bed around 5 in the morning.

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Sunday evening when the risk forecast was written, there was very good confidence in that whatever was coming Tuesday was a threat.  However the weather models did a bit of a 180 on Monday, where at least an inch of snow probability went from 80% to 20% yet even .01 of ice remained roughly the same.

This morning the river fog threat got nullified by the winds that picked up and became strong enough – but less than 100 miles upstream patchy river fog was being reported along the Illinois River and confirmed by traffic cameras in Peoria.  I elected not to make the post before the AM peak and instead focused to watch the models when I woke up to see if the system moving this evening was moving in for the evening peak or holding off for later.

For this southern system it appears that the Gulf of Mexico is not being tapped.

This radar image from a tweet is telling me it has been tapped but not to the degree that causes the big Ohio Valley snow monsters. The SPC does have some Marginal Risk down in Mississippi and Louisiana but not the slight or enhanced risk that potent winter systems often brings.

As a result the forecast around here is up to an inch of snow and .10 of ice – but it will depend on how the system tracks as it goes through Arkansas. The NWS has issued a Winter Weather Advisory that starts at the tail end of the evening peak tonight and expected to last into the morning peak on Wednesday. The timing will be the big factor whether or not the evening peak is dicey or dry. The winter probabilistic were about 50% for an inch of snow and 10% for .01 of ice – a combination of the two is likely. (There is a sharp cutoff of 1% to 70% on .01 of ice between St. Louis and Mt. Vernon when it comes to the storm hitting the Metro East.)

The admins expect the very worst to happen just to the south. Either way it takes very little to cause big problems – and it was the case on Sunday when less than an inch of snow caused massive problems on 44 southwest of St. Louis. The bust potential with this system is still high so if there is one that does happen pray it goes in our favor.

DISCLAIMER – this is just for the system tonight.  The one for tomorrow is still up in the air and will be posted after I get home from work between 01:00 to 02:00 Tuesday morning.

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The image provided from the NWS late this morning is something that the admins were suspecting that Monday evening could happen.  When the risk forecast was written early this morning (shortly after midnight), the possibility was that we were on the fringes of the system moving through Monday evening but at a poor time.  Thus we had the threat at medium for favorable chances.

I stayed up until 06:00 to see what the morning local media was saying and there was no indication from two different TV channels that the threat needed to be upgraded.  Both were still acting like we were on the fringes.

I woke up around 13:00 and the first thing I checked was Facebook.  First thing on my feed was a winter weather advisory issued for this evening for this entire section of 270.  Thus we made the call to upgrade the threat to HIGH for this evening.  The NWS is thinking mist and drizzle with freezing temperatures will be coming in time for the evening peak.

Plan for a nightmare evening peak should the weather move in.  Yesterday a quick shot of snow moved in at a poor time – thankfully it was a Sunday – but in that section of 44 that is just southwest of St. Louis that is in rugged terrain – less than an inch of snow caused four different sections to close between Springfield and Rolla and couple of our other admins were sharing these posts on their personal Facebook accounts:

The emphasis is that it takes very little to cause big problems especially if it falls at a poor time. Given that 270 in North County is rather hilly, once a truck cannot navigate those hills due to the ice big problems can happen almost instantly.

Tonight can remind you what happened in December 2016 – when admins decided to disregard the local TV forecasts to make an emergency post – a decision that paid off here but less than 8 miles to the east of here on 270 was a different story all the way into Effingham.

The National Weather Service has issued a Winter Weather Advisory for this section of 270 that goes in effect later tonight and throughout the entire Monday morning peak period.  While this Monday in question is an holiday and traffic is expected to be lighter than normal, it is still a work day for people in certain occupations.  The temperatures are also expected to bottom out later on Monday and the Tuesday morning peak will be greeted with an Wind Chill advisory, but this bitter cold is expected to be short lived.

In short, up to 2 inches of snow is expected to fall, and most of it is expected to be poor timing snowfall that is projected to be falling prior to the morning peak.

Note: we were hoping for more updated information as we wrote this.


This post has indications of the poor timing snowfall expected.

No risk threat for this week in question has yet to be determined but it is likely Monday and Tuesday will reflect as such.

nws-01112018Earlier in the week medium threat was put in place as models suggested questionable weather moving in late week – for both today and Friday.  While models have determined that this could very well be a two phase event, it is the first phase that the admins are worried about.

The NWS as of 03:51 this morning has issued an Winter Weather Advisory

Phase 1 is expected to hit possibly during the evening peak and this is likely going to bring a wintry mix and a sharp temperature drop.  While severe thunderstorms are not going to be ruled out, the most likely scenario will be rain turning to freezing rain or snow.  (NOTE:  Mother Nature often means business with the dead of winter severe weather and the anything goes nature of winter in this area means all scenarios are on the table for Phase 1.) This phase WILL NOT MISS THIS AREA, so plan accordingly for Thursday afternoon and make wise decisions out there.

Phase 2 is expected to be an all snow event and as of the latest update we are on the fringes of that threat.  This phase will likely be an overnight one and that can make the Friday morning peak quite dicey.  However, Winter Storm Watches are in effect not even 75 miles east of St Louis on 64 and if truckers got any plans towards Louisville or Memphis this system will mean business.

The admins do expect Phase 2 will largely determine on how Phase 1 does (i.e. if Phase 1 moves in slower than expected it can potentially pull Phase 2 further northwest and closer to St Louis.)

As a result the admins are declining to upgrade the risk threat for the Thursday morning peak and the Thursday evening peak and Friday morning peak will depend on what happens with the weather. (A decision for Thursday evening will be made prior to 2 PM and Friday morning sometime between 1 and 4 AM.)

Freezing rain is possible on Sunday during the daytime hours as a system moves in.  While some models have temperatures going above freezing, the ground is ice cold from 14 straight days of below freezing temperatures and “icing from below” is possible.  In fact, while a high risk day is not being ruled out for Monday morning due to this black ice, Sunday is clearly an high risk day.

The NWS has issued Winter Weather Advisories for a reason:

Remember, a forecast like this going bust can have major impact – it takes very little ice to cause massive problems.da496b389be70a2bc33500a95bff97a72f173486b90398fd3be778a65a12822d

While the NWS has only put an Hazardous Weather Outlook for this section of 270 as of 08:30 AM, Winter Weather Advisories are in effect along I-70 west of 270 less than 100 miles away.

freezing drizzle

With an warm front advancing and the ground very cold – along with a light and variable wind, it is possible that mist and inversion fog may develop in advance of a very strong cold front expected to move into the area Saturday morning.  With the high temperatures this afternoon not expected to go above freezing, very little ice has the potential to cause massive problems.  To make matters worse, this stuff is expected to develop in time for the evening peak.  Winter weather that always come in time for a peak period, no matter how weak it is, tends to cause trouble, as it happened last year where .03 of an inch of precipitation caused massive problems thanks to a busted forecast.

There is snow expected less than 150 miles to the north but that white stuff should miss this area.  Following the cold front moving through Saturday the temperatures are expected to bottom out:

While there is still some snow on the ground from last weekend the majority of that snow has either compacted or melted from exposure from the sunlight.

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The bottom line:  while the threat remains at medium, the Friday evening peak will be gross and nasty.  Plan for extra time to get home even though the traffic has been lighter than normal all week due to the Christmas holiday.

Messy holiday weekend expected

Posted: 2017/12/22 in Weather
Tags: ,

futurama-one inch

The NWS has not issued any Winter Weather Advisories but a southern storm with borderline temperatures are expected to make a trip through the region tonight into Saturday morning, and a second system is expected sometime on Sunday morning.

The expected snow is around the 1 inch range with slightly higher amounts just to the southwest. This is the range where the most incidents tend to occur. Crews have been pretreating the roads, given the relatively poor timing of the snowfall. (Thankfully it is hitting the area on a weekend, not a week day.)

In the wee hours of Monday morning when the admins posted the fog risk threat for this week, there was more than enough factors in play to put Thursday morning at HIGH risk:  calm winds, a warm day, cool night, and most importantly temperatures expected to be near the freezing point.  After one of the admins got off work early Thursday morning around 02:00 – the fears were confirmed and by 04:30 the live feed cameras were only confirming what could been happening:

As the morning lows dipped to 28 in Alton the admins made at least two posts on Facebook warning that river fog was present with the freezing temperatures and extreme caution was to be taken.  If that was not enough, Laura Hettiger was running her mouth at least two times during the 05:00 hour on Channel 4 to be aware of the fog threat.  One of the admins went to bed before 06:00 and the other was on the way to work after 05:30 there was not a lot of monitoring on either the Facebook or Twitter accounts.

At or around 06:50, the first of the multiple incidents that happened in a 20 to 25 minute time window happened westbound west of 367 and a second happened eastbound between Lilac and Riverview:

Within 10 minutes this was being reported:

By the way, even around 06:45 there was still river fog in the area of the river bridge by a TV reporter that was making a trip across while en route to an unrelated story:

It was clear that the freezing river fog caused a few slick spots during the AM crunch time and as soon one happened, all shit broke loose.

The river bridge one was in a bad spot too causing crews from Mitchell Fire Department to walk to the scene to get to the people. Luckily only minor injuries were reported in this ordeal.

There were some live videos as well

In the end, the westbound lanes at the bridge were closed for over an hour and it takes at least 90 minutes before things return to normal. The average delay was at least 60 to 90 minutes.  This morning should reinforce why river fog under certain circumstances can lead to the big incidents and all three incidents were consistent with people allegedly driving too fast for the conditions.  In fact, we are approaching the 40th anniversary of one of the first epic fails that happened on this section of 270 and it happened on a morning with freezing temperatures and conditions favorable for river fog.  What happened this morning was minor compared to what happened on the morning of November 12, 1977, and back in the late 1970s there was not much of a morning news scene, no internet, no social media, and everyone relied on the evening newspaper to get their gossip and CB radio for traffic conditions.