National Weather Service United States Department of Commerce

Severe Thunderstorm and Flash Flooding Risks from Southern Plains to Midwest; Heat Wave Developing in the Southeast

Severe thunderstorms and flash flooding will again be possible from the Southern Plains into the Midwest on Friday. Periodic risks of severe thunderstorms, along with flash flooding, are forecast from the Central and Southern Plains to the Great Lakes and Northeast into the Memorial Day weekend. Temperatures across much of the East will run above normal where they will hold into Memorial Day. Read More >

Astronomical Data and Information

Lake of the Woods - Copyright 1999 M.Fuhs

 The July setting sun casts its brilliance
over Lake of the Woods, Ontario

 

The principle of Rayleigh Scattering explains the red or orange sunsets.  As the sun moves lower in the sky, its light has to travel through "more" of the atmosphere since the sun is at a much lower angle.  In fact at the horizons on a level plane, the atmosphere is about 40 times more thick than it is directly overhead.  Particles and molecules in the atmosphere will scatter out the shorter wavelengths (blue in the color spectrum) more easily than longer ones (red).  Thus, we are left with the reddish portion of the light spectrum to see. 

 

 

 

 

 

Season Starting Dates and Times
2019
Spring
Wednesday, Mar 20
4:58 PM CDT
Summer
Friday, Jun 21
10:54 AM CDT
Autumn
Monday, Sep 23
2:50 AM CDT
Winter
Saturday, Dec 21

10:19 PM CST

 

 

2019 Major Meteor Showers
Shower
Period of Activity
Peak Dates
ZHr*
Comments 

Lyrids

April 16 to April 25

Apr 21st and 22nd

 

18

The Lyrids' peak is somewhat brief.  Look in the late evening of April 21st to the early morning hours of April 22nd.  The best viewing will be before sunrise. However, a waning gibbous moon will interfere the brightest meteors during the peak dates. The radiant for this shower is near the border of the constellations Lyra and Hercules.     

Eta Aquariids

April 19 to May 28

May 4th and 5th

 

 

40

Peak time occurs for a couple of hours just before sunrise on May 5th. This shower favors the southern hemisphere and the southern latitudes of the northern hemisphere as the radiant is from near the star Eta in the constellation Aquarius.  In the northern U.S. and Canada, less than 10 to 20 meteors per hour can be expected whereas the shower is quite spectacular in the southern hemisphere.  The moon will be in the new phase; therefore the moon will not interfere with the peak this year. 

Delta Aquariids
July 12 to August 23
Jul 29th and 30th
 
15-20
Peak time occurs from the late evening July 29th through the early morning of July 30th.  Similar to the Eta Aquariids, this shower favors the southern hemisphere and the southern latitudes of the northern hemisphere as the radiant is near the star Delta in the constellation Aquarius.  In the northern U.S. and Canada, less than 15 to 20 meteors per hour can be expected and the meteors are typically rather faint.  
Perseids
August 12 to August 13

Jul 17-August 24

 

50-100
The peak of the Perseids will occur from the evening of August 12th when it gets dark, to the early morning hours of August 13th.  Part of this year's peak time will occur at night for North America from 10 pm CDT on the 12th, to 4 am CDT on the 13th.  The radiant is in the constellation Perseus but meteors from the Perseids are seen all over the sky. Unfortunately, a waxing gibbous moon will provide quite a bit of interference as it will be in the same part of the sky as the radiant. The best viewing will be on a dark sky away from the radiant. Venus and Jupiter will be visible during the late evening on the 12th, while Saturn and Mars will be visible during the overnight hours. 

Orionids

October 21 to October 22

Oct 2 to Nov 7

10-25

Peak viewing will be on the night of October 21-22. The last quarter phase of the moon may interfere the activity, therefore the best viewing will occur before sunrise on October 22.   The radiant is north of Orion's red giant star, Betelguese, but the Orionids can occur anywhere in the sky.

Leonids

November 16 to November 17

Nov 6 to Nov 30

 

15-20

The peak this year will favor the evening hours of November 16th through the early morning of November 17th.  A waning gibbous moon will interfere the activity, therefore viewing before sunrise on the 17th will be best.  The radiant of the Leonids emanate from the constellation Leo. 

Geminids
December 13 to December 14
Dec 4-Dec 17
100-120
Peak viewing will be on the evening of December 13th into the morning hours of December 14th.The best viewing will occur after 9 pm CDT on December 13th, with a peak around 2 am CDT.  Although not as noteworthy as the Perseids, the Geminids are actually usually the best and most consistent shower each year.  The problem is being winter in North America, many times the Geminids are obscured by clouds.  The Geminids' radiant is near the twin's heads in Gemini, but will occur anywhere in the sky.
Quadrantids January 3 - 4, 2020
Dec 27, 2019 to Jan 10, 2010
 
120 Peak time is in the evening of January 3rd to early morning January 4th.  This meteor shower always favors northerly latitudes.  This is because the radiant is near the handle of the Big Dipper in the northern night sky, however meteors with this shower can occur anywhere.  The Quadrantids peak only lasts for a few hours and furthermore this year, a near full moon will provide major interference with this shower.  Therefore observers will see only the brightest meteors with rates much less than 50-100 per hour.

 

DEFINITIONS:

*ZHr =  is the maximum numbers of meteors expected per hour at Zenith (straight up in sky) and under a very dark sky.  Average meteor rate can                 be expected to be less (much less in an urban environment.)

Radiant=  A point in the sky in which meteors appear to originate.

 

 

 

    M16

These pages were developed in response

to public inquiries concerning astronomical data.