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One photo is shown on the 5 pm newscast and one on the 10 pm newscast.

Posted under Hot Shots, Photo

Tonight: Mostly clear. Low: 57-60. Wind: S 5-10 mph.

Friday: Mostly sunny, breezy and warmer. High: 84-89. Wind:  SW 10-20 mph.

Friday Night: Mostly clear. Low: 61-63. Wind: SW 5-15 mph.

Saturday: Mostly sunny, breezy (S 10-20 mph), hot and humid. High: near 90.

Sunday: Mostly sunny, breezy (S 10-20 mph), hot and humid. High: near 90.

Monday: Mostly cloudy with a 40% chance of showers/storms. High: low 80s.

Tuesday: Partly cloudy and breezy (W 10-20 mph). High: upper 70s.

Wednesday: Mostly sunny. High: upper 70s.

Thursday: Partly cloudy. High: near 80.

 

We have had a mostly sunny sky today. Here is the satellite from this afternoon.

The sky will remain mostly clear tonight allowing us to see the International Space Station (ISS) this evening. Here is the information:

Time: 10:28 pm
Duration: 6 min
Location: WSW to NE

 

The forecast remains on course for the temperatures to warm during the next couple of days and for the humidity to increase making it feel more uncomfortable this weekend.  We have had a nice stretch of weather where the dewpoint temperatures were in the 40s and low 50ss…very comfortable conditions…especially for June. The dewpoints are forecast to be in the upper 50s and low 60s Saturday and mid 60s Sunday. Today the dewpoints are low again with higher values to our west. Here is a map shows the dewpoint temperatures this afternoon.

Combine the higher humidity with high temperatures this weekend near 90 degrees and you are going to sweat pretty quickly. A warm layer of air in the mid levels of the atmosphere (Cap) is forecast for Saturday and Sunday. The result will be a mostly sunny sky.

The models are still showing the cold front across eastern Iowa late Sunday night and Monday. The front will slow up during Monday keeping the chance of showers/storms through the day. The map below is the GFS model for 1 pm Monday.

The front will move east Monday night and take the rain with it. High pressure will arrive Tuesday/Wednesday with cooler and less humid conditions.

America’s River Festival in Dubuque
Friday: Mostly sunny. High: mid 80s. Wind: SW 10-20 mph.
Saturday: Mostly sunny and humid. High: near 90. Wind: S 10-20 mph.
Sunday: Mostly sunny and humid. High: near 90. Wind: S 10-20 mph.

Posted under Astronomy, Forecast Discussion

The International Space Station marathon has begun! For people in the northern hemisphere, now is our week to see the International Space Station (ISS) make several (as many as 4 – 5) visible passes in 24 hours. Normally we are fortunate to see the ISS more than a couple times in any night. It usually passes into the shadow of the earth soon after it hurtles above our local horizon or we can see a good high pass maybe once a night; and that is not often.

The orbit of the ISS is inclined 51.6° to the equator. Other than passing over the equator at a diagonal this also means that the farthest north and south the ISS gets is latitude +/-51.6°. The ISS passengers can never see farther north than what Alaska is. Santa is always out of sight, in other words. Any time here in Waterloo we see it very low in the north we can know that it’s over a spot in Canada, at around 52° north latitude.

Here is a graphic I created from a screen capture of a picture generated using a nifty program called Orbitron. I annotated the graphic to illustrate the light and dark parts of a spherical (3D) earth. Because the computer screen is flat (2D), straight lines look curved; hence the reason why the ISS appears to be orbiting along a curved path. *This graphic shows this effect well. The line along which the surface of the earth is where the people there are seeing a sunrise or are seeing a sunset. That demarcation is called the terminator. Look to see that the orbit in this case shows that the ISS does enter the earth’s shadow. It’s not always in light.

This time of year the terminator is tilted about the same as the orbit of the ISS. This causes the ISS to be in constant sunlight over the next few nights. Good time to get a tan up there I suppose. In fact, at this time the astronauts on board don’t see the usual one sunrise and one sunset per orbit. The ISS is high enough above the ground that it can be in sunlight while we are in darkness. It moves overhead during daylight hours as well but since we cannot see it in a bright sky we will not consider those passes.

Even though one can see multiple sightings, some of the visible passes for NE Iowans will be in the far northern and far southern skies. Heavens-above.com provided this example. However we can expect a high pass now and then, during which time the ISS will remain lit up from horizon to horizon! This is a map showing something similar to the pass I saw. On one of those evenings, years ago, I started my ISS marathon by watching the ISS until it was within 1 moon’s diameter of above the eastern horizon! It took braced binoculars to watch it that far away. At that time I observed the ISS pass by 5 times in one 24 hour period. To see the late PM/AM passes I got out of bed over and over again. Here is a graphic showing the ground track of 4 passes that will occur on June 7th, 2012.

The list of visible ISS passes over the next few days is huge. Therefore I have created a screen capture of the table for the Waterloo, Iowa region.
The front page of Heavens-Above shows the current predictions of all sorts of things. Look for ISS and make sure to choose only visible passes to see what is coming for the space station.

For accurate times for your own town, click on this link. Select your location from this map or select your closest town from this database.

*Caption for an above mentioned graphic: Notice what happens to a nice straight line – e.g. the orbit of the ISS – when it’s drawn over the earth as projected in the top graphic. Notice also the break in the orbit on the top left. That break reveals that the earth is turning under the orbiting ISS. It takes the ISS about 1 hour and a half to go once around the earth.

Posted under Astronomy

From NWS
1993: Severe thunderstorms in western and northwestern Iowa produced large hail causing severe damage to car dealerships in Carroll and Estherville, as well as wind gusts to 65 mph which lifted boats from their moorings at Arnolds Park. Several tornadoes also touched down in northwestern Iowa including one which struck Sibley, damaging a house and a high school bus barn.

1984: A significant severe weather outbreak occurred with at least 21 tornadoes touching down in Iowa, mostly in northwestern, southern, and southeastern portions of the state. One tornado produced a nearly continuous damage track for 127 miles over a three hour span, moving from northern Missouri into Iowa just southeast of Lamoni and continuing northeast before finally lifting near Sigourney. This tornado killed 2 people and injured 63 others on its track, with the most intense damage occurring in Mahaska and Keokuk counties where the small towns of Wright and Delta were devastated. The storm weakened in the evening then reintensified after sunset and produced another series of tornadoes in southern Wisconsin later that night, including an F5 that struck the town of Barneveld just before midnight killing 36 people and injuring nearly 200. In Iowa a total of 3 fatalities and 91 injuries were attributed to tornadoes on this day.

1953: Severe thunderstorms produced several tornadoes across northwestern, central, and eastern Iowa. One storm produced a series of tornadoes over a path about 100 miles long from Adair County, east northeast through Polk County just a few miles south of the Des Moines airport, and all the way into southwestern Linn County. At the Des Moines airport a wind gust to 85 mph was measured as the tornado passed nearby.

1901: A very late frost was observed at several stations across northern Iowa including Alta and Fayette. Reported low temperatures included 35 F at Carroll, Clear Lake, Northwood, and Ogden, 34 F at Alta and Forest City, 33 F at Sheldon, Sioux Center, and Spirit Lake, 32 F at Plover and Sibley, and 30 F at Larrabee.

This Day in National/World Weather History …

7 June 1816 → A June snow punctuated the Year Without A Summer in the northeastern U.S. Danville, VT reported drifts of snow and sleet 20 inches deep. Flurries were observed as far south as Boston. 7 June 1936 → Idaho’s deadliest tornado, an F3, killed two people north of Ruebens. A house and a barn were leveled, and the water was removed from a small pond. 7 June 1984 → As part of a massive tornado outbreak in the Upper Midwest, an F5 twister ripped 90% of Barneveld, WI to shreds. Of the town’s 18 business and public buildings, 17 were destroyed. Nine people were killed along the 36 mile long path. 7 June 1998 → On this date, the high temperature at Barrow, AK, on the Arctic Ocean, rose to a record 51 degrees with a gusty land breeze

Posted under Weather History