January 8th, 2010

2010 Annular Solar Eclipse PFS Bulletin No. 2

Published at 23:40. Filed under Precision Forecast Service; no comment so far.

OVERVIEW

This is 2010 Annular Solar Eclipse PFS Bulletin No. 2, issued in both English and Chinese. There is 7 days away from the event, uncertainty for this forecast is small. The forecast diagrams mentioned below may be found at http://7timer.y234.cn/V3/product.php?language=en&product_id=2, https://www.fnmoc.navy.mil and http://www.ecmwf.int. Numeric forecast for various locations may be found at http://7timer.y234.cn/V3/product.php?language=en&product_id=1. RSS feed of this service is available at http://7timer.y234.cn/V3/wordpress/?feed=rss2&cat=46.

ANALYSIS

NCEP GFS JAN08/06Z's forecast shows a significant dry area over Yunnan and Central China on the height of 850mb humidity shows there is a large dry area over Central China and western Indo-China Peninsula. The Mean Sea Level Pressure shows the 1020hPa contour reaches 25N, indicating a mild winter monsoon persisting over mainland China. However, there is no notable feature on 500hPa geopotential height forecast.

ECMWF JAN08/00Z's forecast shows a mild to strong winter monsoon is persisting over Central China as the 1020hPa reaches near 20N, the southern limit of 1030hPa contour is about 2-3 degrees south of the GFS's prediction. Again, no notable feature is shown on 500hPa geopotential height forecast.

FNMOC EFS JAN08/00Z's forecast suggests a weakening winter monsoon with 1020hPa reaches 20N but 1030hPa near 35N. It also suggests a chance of significant rainfall (generally less than 10%) along the path from Ruili to Nanyang at the day time of January 15.

For analyses of the models above, we can depict a persisting but probably mild and/or weakening winter monsoon over mainland.

FORECAST

Since the models have came to a rough agreement on the strength of winter monsoon, the uncertainty of this forecast is reduce to small. Local forecasts are listed below. Please be aware that the forecast philosophy may trim as there is still 7 days to go for the event.

• In Myanmar: sunny, with some haze in valley.
• In Yunnan, China: generally sunny, a few or some clouds to the east, but the cloud amount may still allow an enjoyable observation along the annularity path.
• Around Chongqing, China: foggy, but sunshine is likely over highlands.
• Around Nanyang, China: mainly sunny, the visibility is estimated to be 15 km or better, allowing a reasonably good sky for low elevation observation.
• In Shandong, China: mainly sunny, the visibility is estimated to be about 10-15 km or better, it is possible for observers to get the "fire ring" at horizon.

NEXT UPDATE

January 10 at 1500 UTC or earlier.