Update on drought, rainfall data, and extended forecast

It was the wettest March-May on record for our area, but I am slightly concerned about hot and dry weather in our extended forecast.

Expected response-“but Dave, it’s rained almost every day lately!  We don’t need any more rain! What we need is dry weather and heat!”


Ok, I get it, we do need some dry weather for crops that were underwater.  I hear that, but consider this. A great deal of our moisture was received as snow, sleet, and hail. Do you remember when it hailed for hours back in April? The ground did absorb some of this moisture, but a good part of our early season moisture ran off into rivers rather than the subsoil where we desperately need it since last summer’s drought depleted this resevoir of water. Let’s not forget how frozen the ground was as well.

Here’s the summary of June rainfall so far:

June total for Sioux City: 1.69″          (Avg. is 2.25″)

Year: 15.02″            (Avg. is 12.23″)

Last year at this time we had also seen over 15 ” of liquid equivalent precipitation, but after May the rain basically stopped and the extreme heat and drought depleted virtually all soil moisture by the late summer. What’s different this year is that the subsoil moisture is more depleted, but heat and dry weather has held off until probably the end of this month now.

Notice the improvement in our drought status (earlier this year we were still considered in “exceptional drought”

 Drought status

Check out the extended temperature outlook courtesy of the climate prediction center:

What I see happening is the main storm and rainfall steering jetstream will head up into North Dakota and Manitoba, cutting off our rain chances next week and keeping subtropical air parked over the Plains and Midwest.  For farmers, gardeners, and lawn perfectionists we’ll have to wait and see how this all pans out but get ready for hot weather!

Meteorologist Dave Winslow

Posted under Gardening, Uncategorized, Weather, Weather Blog

This post was written by rdemers on June 18, 2013

Severe weather update and proof of a bountiful month of rain—by Dave Winslow

Yet again we are tracking an unending parade of thunderstorms and severe weather possibilities. I would say this chance is a little better than the last few marginal setups.  The warm front that’s been parked over Northern Kansas will finally get shoved north with a southerly breeze.

Future Track at 6 pm:

 So we will be closer to the w arm sector and extremely unstable air. All modes of severe weather are possible from isolated tornadoes in the evening, to very large hail and damaging wind. Several rounds of storms may move through dumping a few inches of rainfall in some spots.

The SPC forecast is for a “moderate risk” of severe storms (you get a handful of these higher risks each severe wx season):

Rain stats:

The rainfall stats are impressive, and this does not even include Monday night’s rain! I wouldn’t be surprised if monthly totals approach 18″ down south.

Dave Winslow

Posted under Gardening, Weather

This post was written by dwinslow on June 22, 2010

There’s snow… then there’s SNOW! — by Mike Zwier

We are no strangers to snow in Siouxland, especially this winter.  But our snow is nothing compared to the snowstorm that hit the Nation’s Capital this week.

For a look at the troubles this snow has caused the DC community, check out the video below.

Mike Zwier

Posted under Weather

This post was written by mzweir on February 6, 2010

Tropical Weather Update — by Mike Zwier

Here is Siouxland we don’t really have to worry much about what is going on in the tropics unless we’ve got a vacation planned or family that lives in hurricane territory.  Hurricanes can be some of the most destructive and life threatening weather events that we see in the United States, but this year there just hasn’t been too much to talk about.  That may change soon though as a couple good atmospheric waves over the Atlantic Ocean are showing an increased threat of giving us the first named storm of the Atlantic hurricane season. 

The Atlantic hurricane season begins each year on June 1, and we typically see 1-2 named storms during the first two months (June & July).  Tropical dwellers shouldn’t let their guard down yet though.  The most active time for hurricanes is the end of Summer through the beginning of Autumn (August – October).  In fact, according to the National Hurricane Center in Miami, Florida, another recent season with a very slow start was 1992 which brought Florida a category 5 hurricane named Andrew in late August.

During an average Atlantic hurricane season, there are 11 named storms.  Earlier this month the National Hurricane Center revised their initial forecast made in May of a near to above normal storm season.  They are now forecasting a near to below normal season, with 7-11 named storms. 

The main culprit of the decreased activity is the start of an El Nino pattern in the Central Pacific Ocean.  An El Nino pattern increases the upper level wind speeds across the Atlantic Ocean, which inhibits tropical storm development in essence by cutting off the tops of the storms.

Mike Zwier

Posted under Weather

This post was written by mzweir on August 14, 2009

Iffy severe weather risk today, slight chance of frost Sunday AM…

It’s a lot to pack into a weather blog but we are still in the unsettled month of May.  Getting to the severe potential first- the questions we’re still asking revlolve around daytime heating because we will remain mostly cloudy for the majority of the day, and storms to our south are limiting our warming potential to a certain degree.  If we can get some sunshine and temperatures can warm up into the mid to upper 70s, this cold front may put us in business for isolated severe weather in the early afternoon with primarily hail from the stronger storms.  The highest risk will be in Northwest Iowa. 



The frost potential is the other important forecast issue.  Following that strong cold front will be a strong Canadian high pressure that settles in over Western Iowa and Eastern Nebraska Saturday night. 

 If this feature moves in and slows enough, temperatures could dip very close to freezing in some of our river valley locations.  If you have tender plants, I would keep up to date with the latest forecasts and be prepared to cover up your tender garden flowers and veggies.  Have a great weekend.

Dave Winslow

Posted under Weather

This post was written by dwinslow on May 15, 2009

The Long Lost 80’s — by Mike Zwier

No, this isn’t a post about 80’s hair bands or the absence of leg warmers in today’s culture.  Instead, let’s think back to the last time the mercury soared above the 80° mark.  How long do you think it’s been? 

If you guessed 5 or 6 months you’re spot on.  It has been 5 1/2 months since we last hit the 80° mark, on November 3, 2008 Sioux City had a high of 80°.

We should be able to break that streak this week as a strong surge of warm air blows in on Thursday.

It’s not unusual to get an 80° day in April, in fact in 3 out of the last 4 years we saw 80’s earlier than we will this year.  In 2005 and 2007 the first 80° day came in March.

Whatever your plans are for the rest of the week, I hope you can get out and enjoy the warmth at least a little bit since clouds and showers will move in for the weekend.

Have a great day!


Posted under Weather

This post was written by mzweir on April 22, 2009

Winter Storm Hits Misses Siouxland — by Mike Zwier

With the exception of the cold and some light snow and blowing snow, the past couple days have not been too active here in Siouxland.  It is a completely different story for the Southern Plains and Northeast as communities recover from a dose of snow and ice.

Up to three inches of ice accumulated on trees and power lines in parts of the south, and up to a foot of snow caused major travel disruptions across the Ohio River Valley.  I received word from friends in Columbus, Ohio that my Alma mater, The Ohio State University, closed down on Wednesday.  That only happened once while I was an undergrad and grad student there.

In Kentucky, emergency management is reporting nearly 174-thousand customers were without power yesterday due to ice, and the Kentucky National Guard is helping emergency crews remove trees that are blocking roads.

For a closer look at the impacts of the winter storm, check out this video from NBC reporter Michelle Franzen.

Franzen Winter Storm Report

Siouxland has a chance of a light wintry mix, with flurries and drizzle Thursday, but then things calm down and warm up leading into the weekend.  Forecast models are not showing any big winter storms heading our way in the next 7 days, but the forecast for the Northeast includes the possibility for another large winter storm early next week.

Enjoy our late January thaw!

Mike Zwier

Posted under Weather

This post was written by mzweir on January 29, 2009

First 2008-2009 Season Winter Storm? — by Mike Zwier

We have seen some snow fall across Siouxland so far this year, but no storm has been strong enough to be catagorized as a “winter storm.”  Previous snows this season have served as a good brush up for your shoveling skills, and they’ll likely come in very handy by Tuesday morning.
Below is a freeze frame from one of the computer models, showing total precipitation from Sunday afternoon through Tuesday afternoon.  One the zoomed in view, you can see most of Siouxland is covered by a dark green, which indicates between a quarter and half an inch of water based precipitation.  This takes into account rain and melted snow.  To figure out how much actual snow that amounts to we have to do some math.  This time of year we generally see about a 10:1 snow to rain ratio, so if we multiply our total precipitation by 10 we get between 2.5″ and 5″ of snow.  That number seems pretty reasonable for most of Siouxland.
Total Precipitation through Tuesday Afternoon

Total Precipitation through Tuesday AfternoonCloser ViewCloser View


Closer View

Closer View

You may notice that southern and eastern portions of Siouxland are under the dark blue contour.  That indicates between a half and three quarters of an inch of water.  Using the same ratio this equates to 5-7″ of snow.  The heaviest snow should fall right along the line between the dark and light blue from Southwest to Northeast Iowa.  South and east of this line more rain and less snow will fall.  Due to the higher amounts of snow in the blue contours, the National Weather Service has issued a Winter Storm Watch for those areas, including southern parts of Siouxland. 


Winter Storm Watch -- Monday & Tuesday

Winter Storm Watch -- Monday & Tuesday


In addition to the snow, we can expect very gusty winds on Tuesday, which will create travel difficulties due to blowing and drifting snow.  If you do have to travel make sure to give yourself some extra time, and take it nice and slow.  For updated road conditions, check out the weather section at KTIV.com.  There are links to South Dakota, Iowa and Nebraska road conditions about half way down the page.  
Mike Zwier

Posted under Weather

This post was written by mzweir on December 7, 2008