On the weather front… many interesting events are on the horizon. A strong upper storm system in the southwest U.S. is forecast to move eastward through the southern Plains. Another storm in Canada will dive southeastward toward the Great Lakes. These two storms will be responsible for several weather changes during the next four to five days.
Scattered showers and thunderstorms are already organizing in southern Oklahoma this morning as moisture increases in advance of the southwest U.S. storm. Precipitation should become more widespread by this evening and continue through Thursday. Before it ends Friday morning, some places in the state could see over four inches of rain. While it does look like the heavier rainfall will be in eastern Oklahoma… Okarche stands to see a couple of inches.
The first of a couple of fronts will clear the state Friday morning and we will be left with a fairly nice and cool evening. A much stronger cold front will surge into the state Saturday morning. Behind this front… winds will become quite strong out of the north and temperatures should fall to the lowest levels so far in this early Fall. The low temperature Sunday night should make it well below 40 degrees with the first frost possible.
On the astro front… a couple of events will be taking place this month. A close conjunction on October 13: Around 5:30 a.m. Venus and Saturn will pop up in the eastern sky – separated by less than ½ degree. Venus on the right will be a bright -3.67 magnitude… Saturn on the left will be around 1.39 magnitude. Mercury makes its appearance about an hour later at -0.95 mag.
The Orionids Meteor Shower will run from October 17 to 25. While this shower typically produces only about 20 meteors per hour during its peak… viewing this year will be nice as a waxing crescent moon will set early. Any clear nights should be well dark providing an excellent opportunity for viewing and photography.
Finally, Fall foliage. We are not that far away from color change here in Oklahoma. It’s actually already started… but should kick into high gear soon. Last year I took a trip to southeast Oklahoma. This year, I think I will be spending a couple of days at four spots west of Highway 81. If all goes well… a day will be spent south of I-40 in the Wichita Wildlife Refuge and around Red Rock Canyon State Park. Another day will be set aside for areas around Roman Nose State Park and Great Salt Plains State Park to the north of I-40.
Afternoon temperatures did make it well into the 90′s across a large part of Oklahoma this afternoon… 96+ over much of north central and western Oklahoma and even 100 degrees in a couple of spots. In Okarche… the 94 degree high temperature fell three degrees short of the record.
I went to the roof for photography of the International Space Station as it made its flyby at 8:06 p.m. It took about 2 1/2 minutes to cross the sky from the northwest to southeast. I was happy to see and catch a flare as it first came into view left of the Big Dipper:
I spun the camera around to catch the rest of the trip and fade as it slid between the Moon (68%) and Jupiter:
How can it be so warm? One of the best situations to get rapid warming in Oklahoma this time of year is going to unfold today. A strong cold front will be approaching from the north as a storm system lifts to the north of the Great Lakes. In advance of this front… winds will veer around to the southwest bringing a warm and dry/downslope wind out of New Mexico and west Texas. This is usually the only way temperatures in Oklahoma can reach 100 degrees this time of year. While that may be a reach today… especially with all the recent rain and current greenness… temperatures should still warm to levels that will make you want to check the calendar and make sure it’s fall. The afternoon high temperature in Okarche should come in just a few degrees below the record – at around 91 degrees. In southwest Oklahoma… temperatures may well approach the 100 degree mark. It will be dry, and the sun doesn’t have near the high angle or duration to make things as miserable as it would if it was July. So, we can all call it a pleasantly warm day that will probably require the A.C. being turned on for a bit. The front will come through tonight which will swing the winds to the north and bring our temperatures back down to near or below normal for Monday. Below is a forecast map for 6 p.m.’ish Sunday afternoon which gives a visual description of how things should unfold. I will update this post with a high temperature map later and we’ll see how well our forecast did.
But it already feels like it. The first decent cold front of the season got here about 24 hours ahead of the calendar. That’s still not too bad I suppose. I woke up this morning to a chill in the air and the AC wasn’t even on. 52 degrees outside right now with cloudy skies, light rain and a brisk northwest wind. Ahh yes, it’s a great time of year. Fall officially begins at 4:18 p.m. this afternoon. We will continue to lose at least a minute and a half of sunlight each day now through November 19th. The color change is just around the corner… the high summer electric bills are done… and the yard will quit growing. I love this time of year.
One of my many projects has been organizing my climate data. Recently completed has been figuring daily rainfall averages for the period 1982-2008. The result is seeing how we stack up to a normal year. 2009 started below normal and fell well below normal before rapidly making up ground over the past couple of months. On September 12… we made it above normal for the first time this year. Barely. The bit of rain today should help us stay there for a few more days. The following chart will soon be added and updated daily on my webpage:
An upper level low pressure area that moved north through Texas has brought some heavy amounts of rainfall to Oklahoma during the past few days. Okarche was one of the spots that took advantage of the tropical atmosphere and recorded a good deal of rain. 3.77 inches of rain has fallen during the past three days and light rain continues at this hour. Most of that precipitation (3.51 inches) fell on the 12th, breaking a 20 year old record for the date by 0.01 of an inch. This was also enough to make the top 10 list for daily rainfall (#9). As one would expect, temperatures have been below normal through much of the first half of the month – 10 of 13 days.
Speaking of temperature normal’s – September is the first month that you will see a change in how the monthly climate data for Okarche is displayed. Changes include the addition of daily temperature averages and departures from normal… as well as a little more detailed wind data.
While buckets of rain have fallen in several areas… some have not been as lucky. In fact, downright unlucky if you wanted rain in places like western Logan County (about 20 miles to our northeast). Radar rainfall estimates are not exact… they frequently come in too high and sometimes lower than the actual amount verified by rain gauges. However, this rainfall event seemed to be handled very well – especially in Kingfisher and Canadian Counties where the radar beam from the Twin Lakes radar is about 3500 feet above the ground. Actual observations from El Reno, Okarche and Kingfisher were very close to the radar estimates. With that in mind… we can look with higher confidence at the data in the image above. This estimate of rainfall shows some “hot spots” where rainfall likely reached five, six or even seven inches over the past few days close to Okarche. It also shows the hit and miss nature of the heavier precipitation around places east of Okarche that have likely recorded less than 1/4 of an inch.
The high temperature today in Okarche was 87 degrees. Significant in that this is the 11th day in a row where the temperature has not reached 90 degrees. Almost unbelievable for late August and early September. On August 31st… the low temperature reached 55 degrees which set a record for the month of August.
While it looks like we may warm up a little over the next few days… temperatures shouldn’t get out of hand. Model data suggests a cooler and wetter late week and next weekend. For all practical purposes, it looks like we can stick a fork in summer – as far as high heat goes.
Wildland fires in California over the past 10 days have produced a steady stream of high level smoke that found its way into the plains. This created hazy afternoon skies… but brilliant sun and moon, sets and rises. Attached are a few images taken during the past week…
The wild summer continues! A front moved into Oklahoma on Wednesday the 26th and provided the focus for yet more thunderstorm activity. With high to extreme instability – it didn’t take long for some of the storms to become severe. Some large hail was reported… however, strong and damaging winds were the most common form of severe weather. I first targeted storms near Watonga – but they weakened shortly after my 30 minute drive into Blaine County. Soon after, intense convection began forming just to my southeast in southwest Kingfisher County. At 6:10 p.m… I watched a landspout tornado form just east of the Blaine/Kingfisher County line near Altona. Landspouts can resemble tornadoes but are usually weak, form in environments with generally weak winds and strong instability – and are not usually associated with a pre-existing meso-cyclone. The event lasted about 11 minutes:
The storm that produced the spout rapidly intensified and produced damaging winds as it moved into Canadian County. There was also likely some large hail given the radar signature – but I didn’t get to sample any of that.
Later, I was treated to a beautiful sunset about 5 miles southeast of Okarche. Shortly after sunset… new storms began producing impressive lightning to my west and southwest. I was able to grab a few shots with some sunset light still in the picture.
Another 1.09 inches of rain has brought the August total to 8.60 inches. It doesn’t look like this will be the wettest August on record… but it has sure been one to remember.
Supercell thunderstorms spread across Illinois during the afternoon hours of August 19th… producing several tornadoes and quite a few injuries. Damage surveys are still being completed…but below are some radar captures and brief descriptions of some of the events. Click on image for complete view…
Thanks to a total of 3.55 inches of rain from the 17th until the 20th… this August has become the second wettest August in Okarche. We are a long way off being the wettest August… and it doesn’t look like too much more precipitation is in store for the rest of the month. Things can change, but how it stands now:
1996 – 11.08 inches
2009 – 7.51
2008 – 7.33
1989 – 7.20
2007 – 6.84
The next week looks mild and dry with lows during the next couple of days making it down below 60 degrees. Afternoon highs should not make it past the low 90′s. Longer range models hint at a chance of rain during the last couple of days of the month.
We made it out storm chasing once again on the 19th and watched a few storms in northwest Oklahoma. They didn’t produce a very long show for us… but we were able to grab a couple of lightning pictures before they died. Other storms that formed in Kingfisher County stayed just out of our reach for other lightning ops… but did look nice for the couple of hours that we followed them.
A great August chase day! I usually spend the summer months just hoping for storms that will produce good lightning ops… but on Monday (17th), we got lucky with not only nice lightning – but good supercell structure to go along with it. The atmosphere was extremely unstable with surface based CAPE in excess of 5000 j/kg over parts of northwest Oklahoma. Mid level flow wasn’t the greatest….but was about 25 knots. The two combined to produce several severe storms – some of which produced significant severe weather just northwest of Okarche. The first storm we took a look at was just northwest of Watonga. This storm had some decent structure for a bit and had a rotating wall cloud that opened eyes. When this storm was undercut by outflow which spread to the southeast…. another storm formed just southeast of Watonga. This storm quickly became severe and exhibited supercell characteristics right from the start. It didn’t move very quickly… lazy would be the best way to put it… as it headed southeast around 5 mph. Before it made it into Kingfisher or Canadian Counties… it started getting strong development on it’s southwest flank… which caused it to drift southwestward toward Geary. The end result was us watching a severe storm about 10 miles from where we first started our chase. The storm itself was incredible! The supercell structure that it displayed was some of the best you could ever expect to see anytime of the year. And the lightning that it produced was extremely impressive and fairly easy to photograph. Below is a radar image of the storm when it looked it’s best visually. Also… an image from about the same time. This supercell stayed just west of Okarche and we only received 0.17 inches of rain from it. Later that night (18th) and into the morning hours… another 1.89 inches of rain fell which set a record for the date. Yes, things continue interesting around here – and as I type… a line of severe storms is moving east through the western part of the state.
Other images from the chase can be found at http://www.pbase.com/okweatherwatch/081709
It doesn’t appear that this month will make it to the wettest month on record… but it won’t take much to reach the number two spot…
The most rainfall for the month of August in Okarche:
1996 – 11.08 inches
2008 – 7.33
1989 – 7.20
2007 – 6.84
2005 – 6.25
2009 – 6.02