A snowstorm in Colorado has already dumped over two feet of snow in central of Colorado today, including the Denver - Boulder - Fort Collins area, and it's still coming down. Over 40 inches accumulated in the higher elevations. Blizzard warnings (red) are currently in effect for northeast Colorado including Limon and Sterling.
Winter storm warnings are in pink, winter weather advisories are in purple, and freeze warnings are in light blue. Severe weather watches (yellow) are in effect for the lower Mississippi valley, while various flood advisories extend into Missouri Iowa and Illinois.
Hurricane Rick in the Eastern Pacific is now a category 5 monster. The estimated minimum central pressure is 906 mb (26.75 inches)...maximum sustained winds estimated at 180 mph...with hurricane force winds extending out to 45 miles from the center and tropical storm force to 155 miles. Rick is the second strongest hurricane on record in the Eastern Pacific. A wider view:
And a visible image from earlier today:
Although Rick currently moving westward, a trough is forecast to dig into Southern California by Monday and turn Rick to the north. GFS has been consistent with moving Rick into Southern Baja by late Wednesday and NHC concurs:
Meanwhile, a polar airmass with dewpoints in the 30s had prompted frost advisories (in blue) and freeze warnings (light blue) across the Ohio Valley and Southeast.
Freeze warnings cover almost all of Ohio, most of Missouri, The Appalachians down to extreme Northeast Georgia, and even the County north of Tulsa, Ok. Frost advisories are in effect for most of Illinois, Indiana, Missouri, Kentucky, and Tennessee including Nashville and Chattanooga. Freeze watches (dark blue) go down to parts of Mississippi, Alabama including Birmingham, and Georgia including Atlanta and even to just two counties north of Macon. Dewpoints are now in the 30s even on the Gulf Coast.
At station 42363, about 100 miles south of New Orleans, the dewpoint fell to 42.1. I am reminded now that this same station measured a dewpoint of 55F (12.8)C back on August 23rd. It should be noted that this is a drilling platform with measurements taken at a height of 37 meters as opposed to the more standard 4. Even so, the dewpoint at 4 meters at station 42039 115 nautical miles southeast of Pensacola was 57 0n August 23rd and 47.7 at 1AM today - and an air temperature of only 60.4 currently. This cool airmass has swept through the entire Gulf of Mexico.
Buoy 42055 in the Bay of Campeche recorded a temperature drop of almost 7 degrees.
Even though this buoy is at 22 latitude, the front was still strong enough to produce 35 knot wind gusts and sustained winds at over 3
Also, Eureka, Canada on Ellsemere Island already hit -20 degrees on Oct. 17th. It went down to -22 at 8PM with a dewpoint of -31.
Buoys as far south as 36.789 latitude - south of San Francisco - (buoy 46042, 42.7 knots) have recorded gusts over 40 knots. The highest wind gust that I found was buoy 46014 with 44.7 knots at 39.196 latitude. Over land however, a wind gust of 72 mph was reported at Pike County Lookout - north of Sacramento and almost exactly straight east of buoy 46014 - at an elevation of only 3714 feet. Flood advisories have been issued as far south as Los Angeles.
Freezes are being reported about 200 miles beyond the median freeze line for Oct 12.
To put it another way, the median freeze line is actually close to the 28 degree line. This would suggest that lows are about 4 degrees colder than normal along that line, which is true - but the highs have been 8-18 degrees below normal in those same areas.
The reason highs are affected more is that clouds accompany such a strong cold airmass. In fact, most of the entire country was cloudy today.
It has been suggested that increases in cloud cover amplify the cooling effect of a decrease in solar activity by reflecting radiation away. This certainly seems plausible given how cold and cloudy it has been, and given the fact that the sun has been very quiet for over two years now.
And Poland, The Czech Republic and Slovakia might see blizzard conditions by Wednesday morning.
Freeze warnings now extend to Springfield and Quincy in Illinois, Jefferson City (not shown, underneath flood warning) and Kansas City in Missouri, Medicine Lodge in Kansas, Woodward in Oklahoma, and the Texas panhandle, where record cold is expected. The southeastern Texas panhandle has normal freeze dates going into November. A frost advisory is in effect for Indianapolis.
Buoy 46078 in the Gulf of Alaska recorded a 48.6 knot wind gust last night.
Buoy 46066, 380 nautical miles southwest of Kodiak, recently reported 28.9 foot waves with winds gusting to 46.6 knots.
Frost advisories (darker blue band immediately below freeze warnings) extend even further south and now include Peoria and Quincy in Illinois, Kansas City in Missouri, and Hutchinson, Dodge City and Garden City in Kansas. According to the Farmer's Almanac, the average frost date for Chicago is Oct. 24, for Quincy is Oct. 22 and for Kansas City is Oct. 28. Freeze watches include Amarillo, Tx and Woodward, Ok. The light blue in Arkansas is for flood advisories (not freeze warnings).
It is not much bigger than New Jersey. Over the last several years, NHC has been increasingly naming everything in sight. This particular example goes a long way toward showing this trend. Water vapor imagery shows the original disturbance rotating around the back(west) side of a large mid/upper trough stalled out over the Azores:
Over such cool waters, deep convection can only be supported by the steep lapse rate environment provided by the mid-level trough.
A moist adiabat from 21 C at sea level will only reach around -8 C at 500 mb. If that parcel were placed in the tropics, where 500 mb temps are seen to be about -5 C, this would be likley produce a positive lifted index.
Another non-tropical feature is the horizontal thermal contrast - although given Grace's small size it might be argued that the storm itself doesn't even cross more than one isotherm.
Even with systems like this being named, tropical activity in the Atlantic should be below normal this year.
