A clear night over the Great Lakes — associated with a large High Pressure System, shown below in the 0600 UTC Surface Analysis — allowed a high-resolution view of Lake Surface Temperatures. There are thin filaments of colder waters hugging different coastlines: the eastern shore of Lake Michigan, the western shore of the Upper Peninsula of Michigan, the southern shore of Manitoulin Island in northern Lake Huron. In these regions, off-shore winds are likely causing deeper (colder) sub-surface waters to upwell. The National Weather Service in Duluth noticed a similar event on 23 July (link to Twitter/X).

Do you think those surface temperatures are warmer than normal as a whole? The purple enhancement over Lake Superior shows temperatures cooler than 60^oF. Michigan and Huron show temperatures around 70^oF (green) except for Saginaw Bay, where it’s in the mid-70s. Western Lake Erie is 77-78 ^oF; Lake Ontario is around 75^oF at its warmest point. GLERL maintains line plots of basin-wide averages: Superior, Michigan, Huron, Erie and Ontario. All five lakes are warmer on 25 July than the long-term average.

View only this post Read Less

Typhoon Gaemi took a very unusual path on its route to a landfall along the eastern shore of Taiwan on 24 July 2024. HImawari-9 Clean Window infrared (Band 13, 10.4 µm) target scene imagery, below, (here is a shorter animation (animated gif) animation than the mp4 below) shows the storm moving northwest, then west, then south along the east coast of Taiwan before looping into the coast and making landfall. By the end of the animation (2252 UTC on 24 July), the storm has moved off the northwest coast of Taiwan. The unusually wobbly path is also very apparent in this radar animation (courtesy Brian McNoldy (Univ of Miami))

Microwave imagery at 0923 UTC on 24 July 2024, below, taken from the SSEC Tropical Weather Website, show a well-defined eye with rainbands surrounding the storm. Shear values (850-200 mb) are also plotted on the image and are small over the storm.

Total Precipitable Water fields (source) for the 24 hours ending at 1300 UTC on 24 July 2024 show Gaemi embedded within a region of rich moisture over the Western Pacific Ocean basin. However, by the end of the animation, dryer air from Asia is starting to wrap into the southern part of the storm circulation.

Gaemi’s future path takes it over mainland China.

View only this post Read Less

There are many examples of NOAA‘s GOES ABI detecting the spectral signatures of large rockets. These include GOES-S, GOES-T, GOES-U, GOES-U boosters, Starliner, Falcon 9, Ariane, Himawari-9, Antares, etc. If the rocket is large enough, there is often a signal in each of the 16 ABI bands. Of course the timing of the ABI scan needs to correspond to the times of the rocket’s brightest / hottest phases, which is more likely if there’s a meso-scale sector covering the area of interest, either at 1-min or 30-second cadence.

Smaller rockets, such as the Firefly, may be be an order of magnitude darker/cooler compared to a Falcon, given their very different maximum thrust. The Firefly maximum rocket thrust is approximately 165,000 lbf (pound-force) [736.1 kN] and the Falcon 9 is about 1,700,000 lbf [7,000 kN].

Firefly on July 4th

Late on July 3rd (local time, early July 4th UTC) there was a Firefly rocket launch from Vandenberg Air Force base.

?#ICYMI: Firefly's #NoiseofSummer Alpha rocket lifted off from SLC-2 at Vandenberg Space Force Base in California at 9:04pm PDT July 3/12:04am EDT July 4.

On board were 8?? small payloads for NASA’s CubeSat Launch Initiative! pic.twitter.com/qRCLVFceGI

— NASA's Launch Services Program (@NASA_LSP) July 5, 2024

Given the smaller rocket size, a fair question is if it can be seen by the GOES ABI. Often the “Meso 1” sector from GOES-West covers most of California (the default location for this sector). This was the case on July 3, into July 4, 2024. A first look at the 16 spectral bands on the ABI, using default enhancements, shows no discernible rocket plume signature. (The signal of the explosion on the maiden Firefly rocket flight was seen by each band of the ABI.)

Yet, a highly-enhanced (stretched) ABI band 5 (1.61 micrometers) showed a glimpse of the rocket launch. (Some instrument noise is also seen.)

The rocket signature is more evident in the nighttime micro-physics RGB combination. Watch near the coast for the first signature.

While it’s hard to tell, there may be some indication of the plume in the 11-12 micrometer split window difference from the CONUS sectors.

H/T

The GOES ABI data was accessed via the UW/SSEC Data Services. McIDAS-X, geo2grid and AWIPS software were used to generate the images. More UW/CIMSS Satellite Blogs associated with rocket signatures. T. Schmit works for NOAA/NESDIS/STAR and is stationed in Madison, WI.

View only this post Read Less

As noted here, CSPP software now includes the ability to show reprojected values of Aerosol Optical Depth, in this case within AWIPS. The AOD from the NOAA-20 afternoon pass on 21 July shows extensive smoke over the Plains of Canada and the northern Plains of the USA. Clean air is confined to the Upper Peninsula (UP) of Michigan. The Day Night band imagery at the same time is more distinct over the UP as well. Note, for example, how easy it is to see Lake Superior compared to Lake of the Woods on the Minnesota/Canada border, or Lake Manitoba.

AOD computation with VIIRS data requires visible bands that give no information at night (the ATBD for VIIRS AOD is here). Day Night Band imagery — with a near-full moon — gives information on smoke distribution based on, as above, how well surface features can be viewed.

VIIRS data from the CIMSS Direct Broadcast site — the source of these AWIPS images — can also be viewed online here.

---

VIIRS AOD from the afternoon overpass on 22 July 2024, below, shows a general increase in AOD values over the midwest as the region of relatively clean air over the western Great Lakes shrinks.

Earth-based observations at Madison from this site show the evolution of the particulate matter from 17-22 July. There is an increase an lowering in the particulates over the course of time. In particular, a defined layer near 4 km becomes apparent by 19 July 2024.

The smoke layer is also apparent in the series of small plots shown below, starting high in the atmosphere on 18 July, and descending to around 4 km on 19 July. A lower-layer of particulates was also present on 19-21 July 2024; showers on the 21st likely removed that lower layer.

---

GOES-R Satellites also produce the Level 2 product Aerosol Optical Depth. The animation below shows GOES-derived values from 1756-2201 UTC on 22 July. The data are produced every 5 minutes, and the extensive smoke pall is captured.

Four VIIRS overpasses occurred during the 5 hour animation shown above. The four toggles below compare the VIIRS and GOES-R AOD. The VIIRS product on this day shows more coverage. This is likely related to the different cloud masks.

View only this post Read Less