Intense Eastern Pacific / Gulf of Alaska storm

April 2nd, 2012
GOES-15 6.5 µm water vapor channel images (click image to play animation)

GOES-15 6.5 µm water vapor channel images (click image to play animation)

McIDAS images of 4-km resolution GOES-15 6.5 µm water vapor channel data (above; click image to play animation) displayed the development of a classic “dry swirl” water vapor signature indicating the transition to an occluded cyclone during the 01 April – 02 April 2012 time period. The Ocean Prediction Center was forecasting large areas of hurricane force winds associated with this storm (00 UTC | 06 UTC | 12 UTC).

A sequence of AWIPS images of 1-km resolution MODIS 11.0 µm and POES AVHRR 12.0 µm IR channel data (below) showed a variery of small-scale banding structures during various stages of development of the storm.

MODIS 11.0 µm + POES AVHRR 12.0 µm IR channel images

MODIS 11.0 µm + POES AVHRR 12.0 µm IR channel images

The approach of a strong Potential Vorticity (PV) anomaly helped the storm to intensify rapidly, with with CRAS model fields indicating the tropopause (taken to be the pressure level of the PV1.5 surface) lowering to around the 900 millibar level by 06 UTC on 02 April (below).

GOES-15 6.5 µm water vapor images + CRAS model PV1.5 pressure

Although the storm was near the edge of the GOES-15 sounder scan, an image of the GOES-15 sounder Total Column Ozone product (below) showed that the PV anomaly was situated along a strong ozone gradient (which is often the case).

GOES-15 6.5 µm water vapor image + GOES-15 sounder Total Column Ozone product (with overlays of CRAS model PV1.5 pressure)

GOES-15 6.5 µm water vapor image + GOES-15 sounder Total Column Ozone product (with overlays of CRAS model PV1.5 pressure)

The MIMIC Total Precipitable Water (TPW) product (below) showed the storm tapped an area of moisture that was situated north of the Hawaiian Islands, eventually stretching this moisture into a thin filament along the storm’s cold frontal boundary.

MIMIC Total Precipitable Water product (click image to play animation)

MIMIC Total Precipitable Water product (click image to play animation)

Later in the day, an overpass of a EUMETSAT MetOp satellite provided ASCAT ocean surface winds over the large occluded storm as it was moving slowly off the coast of British Columbia, Canada. A comparison of 1-km resolution MODIS 0.65 µm visible channel and MODIS 11.0 µm IR channel images with an overlay of ASCAT wind vectors is shown below.

MODIS 0.65 µm visible channel and 11.0 µm IR channel images + MetOp ASCAT scatterometer surface winds

MODIS 0.65 µm visible channel and 11.0 µm IR channel images + MetOp ASCAT scatterometer surface winds

Posted in AVHRR, GOES sounder, GOES-15, Marine weather, MODIS, POES, Satellite winds | No Comments »

GOES-15 is operational once again

March 23rd, 2012
GOES-13 + GOES-15 6.5 µm water vapor channel images (with surface analyses and buoy reports)

GOES-13 + GOES-15 6.5 µm water vapor channel images (with surface analyses and buoy reports)

GOES-15 was restored to operational status mid-day on 23 March 2012 (after a satellite outage that began after 20:30 UTC on 21 March). Using AWIPS, a sequence of  GOES-13 6.5 µm water vapor channel images early in the day, followed by the return of GOES-15 6.5 µm water vapor channel images (above) showed the dramatic improvement in the appearance of features associated with a large mid-latitude cyclone over the East Pacific Ocean. This cyclone was producing Storm Force winds over the open waters of the Pacific, as well as Gale Force winds off the coasts of California and Oregon.

McIDAS images of GOES-15 0.63 µm visible channel data (below) portrayed the large size of this storm system.

GOES-15 0.63 µm visible channel images (click image to play animation)

GOES-15 0.63 µm visible channel images (click image to play animation)

Shown below is an HD-format version of an animation of GOES-15 0.63 µm visible channel images (courtesy of Tim Schmit, NOAA/ASPB/CIMSS).

GOES-15 0.63 µm visible channel imsage (click image to play animation)

GOES-15 0.63 µm visible channel imsage (click image to play animation)

Posted in GOES-13, GOES-15, Marine weather | No Comments »

Warm water temperatures in the Great Lakes

March 21st, 2012
MODIS Sea Surface Temperature product

MODIS Sea Surface Temperature product

On 20 March 2012, the Milwaukee/Sullivan NWS forecast office posted a story about possible record warm water temperatures in southern Lake Michigan. Then, on 21 March 2012, the Lake Erie water temperature measured at Buffalo, New York was 39º F, which tied for the warmest water temperature ever measured there during the month of March (Lake Erie water temperature records).

An AWIPS image of the MODIS Sea Surface Temperature (SST) product (above) showed that there were a number of pockets of warm SST values in the 50s F (green to yellow color enhancement) within Lakes Michigan, Huron, Erie, and Ontario, with only a few isolated SST values in the 30s F (darker blue color enhancement) in each of those lakes.

Posted in Marine weather, MODIS | 1 Comment »

« Older Entries