July 25, 2014
A cold front and trailing upper level disturbance will spread showers
and thunderstorms eastward across the Midwest from Friday through
Sunday. The models continue to show the heaviest rains likely east of
the Mississippi River, while rainfall will be generally light and
spotty across the mid-MS and lower-MS valleys. This feature will lead
to spotty showers and storms across NE and northern KS tonight and
Saturday with more numerous showers and storms expected from southern
KS to TX on Sunday and Monday. A disturbance will trigger showers and
storms from western NE and KS to TX and LA from later Tuesday into
Thursday. Upper level disturbances rotating through the vigorous upper
trough that digs into the Midwest early next week will result in
scattered showers and thunderstorms across the Midwest from Thursday
into next weekend. The trough over the Midwest will weak and lift
heading into the 11-15 day period which should allow for a brief warm
in the 11-15 day period. However, there are still no signs of
prolonged extreme heat across the Midwest through at least mid-August.
The models continue to vary on rainfall details in the long range, but
the consensus of the modeling suggests rainfall will be 75-100% of
normal across the Midwest in the 11-15 day period.
A cluster of showers and thunderstorms associated with an area of low
pressure about 1,600 miles to the southwest of the southern tip of
Baja California continues to drift westward. This feature is moving
into a region that is more favorable for development and will probably
become a depression during the next day or two.
A tropical wave west-southwest of the above area, about 950 miles
southeast of the Big Island of Hawaii, is producing a cluster of
showers and thunderstorms in its vicinity. While this will be unlikely
to form over the next 24 hours, in the longer term, development may
become more likely and will need to be monitored over the next few
A disorganized area of showers and thunderstorms south of the
southeastern coast of Mexico shows little signs of development anytime
during the next 24-48 hours. Beyond that time frame, this feature may
become better organized.
A weak frontal boundary can lead to a few light showers along the
coast of BA later Friday and Friday night; otherwise remaining dry
elsewhere across Argentina. High pressure will foster dry weather
across Argentina from Saturday through Monday. A frontal boundary will
lead to scattered showers and thunderstorms from BA to Formosa and
Chaco on eastward from Tuesday into Thursday. Another front will
spread scattered showers and thunderstorms northward across the
Argentina croplands next Friday and Saturday. Drying out in most areas
next Sunday, but scattered storms can linger near the Paraguay border.
An overall drier pattern is expected across Argentina in the 11-15 day
period, but there can be a frontal passage later in the period. Across
Brazil, A stalled front will lead to isolated to scattered showers and
thunderstorms from SP and MGDS on northward from Friday through
Monday. Isolated showers can linger across Minas Gerias and Goias on
Tuesday. A few showers can reach as far south as Parana on Monday;
otherwise most areas from RGS to Parana will have dry weather through
Tuesday. Another slow-moving front will lead to scattered showers and
thunderstorms from Thursday through next Sunday. A few showers and
storms will reach Parana next weekend; otherwise dry across Parana,
SP, and MGDS from Tuesday through next Friday. Dry weather will
prevail across Minas Gerias, Goias, and Mato Grosso from Wednesday
through next weekend and likely through the 11-15 day period.
As of Friday morning, EDT, Tropical Rainstorm Matmo will continue
through Northeast China and will continue to cause flooding over
portions of Liaoning, Jilin, and Heilongjiang before continuing
northeastward to northern Japan on Saturday night into Sunday. Despite
weakening rain will range from 2.00-4.00 in the southeastern areas
with locally up to 6 inches. This rainfall will also fall across
northern North Korea.
Meanwhile, an area of convection is centered near Palau. Vertical wind
shear is preventing development at this time and is likely to continue
doing so for at least another 12-24 hours.
A weakening monsoonal low will lead to scattered rains and
thunderstorms across western India into far eastern Pakistan on
Friday. Monsoonal rains will retreat eastward out of these areas this
weekend with limited rainfall expected across western India early next
week. Another westward surge of monsoonal moisture toward Pakistan is
possible late next week.