Temperatures over Ahmedabad during winter season
Normal Temperatures
The winter season in Ahmedabad starts from the month of December with Normal
minimum temperatures falling to around 13° C .The normal minimum temperatures fall
from about 19 °C in the beginning of November to 14° C towards the end. They fall to
12° C by the end of December and maintain around 12° C till January last week and
thereafter they start increasing steadily to reach 15° C by the end of February. The day to
day normal minimum temperatures from November to February are given in Fig.1.
Extreme Temperatures
There are few spells in every season when the minimum temperatures fall 4 to 6°C below
their normal values leading to cold wave conditions. Since December and January are the
coldest months in the season, the lowest minimum temperatures recorded in each of these
months during 1991 to 2009 are given in table.1.The table indicates that minimum
temperatures during December fall to about 9- 10 °C and those during January to 7-8° C
during most of the years. The all time record for minimum temperature over Ahmedabad
for the month of December is 3.6°C recorded on 27 December 1983 and that for January
is 3.3° C recorded on 10 January 1958.
Temperatures during 2010 so far
The winters of 2010 started on a warmer note with the minimum temperatures
during November remaining above normal on most of the days of November .The mean
maximum and mean minimum temperatures for the month of November 2010 were
31.0°C and 20.6° C against their long period average of 33° C and 16.5° C. The lowest
minimum temperature of 16.7° C was recorded on 23 November 2010. The minimum
temperatures during the first week of December have been hovering around 16 to 17° C
which is 2 to 3° C above normal. The temperatures have dropped to normal values from 8
December. The day to day minimum temperatures from 1 November to 10 December are
given in Fig.1 below.
Outlook for the December month
The mean temperatures for the month of December 2010 are expected to remain below
normal. The experimental extended range forecasts of IMD for the month of December
2010 indicates, that the probability of below normal maximum and minimum temperature
is high (70 to 90 %) over Gujarat State (Figures 2 and 3)
Table1. The Lowest minimum temperatures recorded during December and
January
Year
January
December
1991
1992
1993
1994
Temp.°C
4.8
4.8
9.8
8.9
Date
2 .0
6.0
22
15
Temp.°C
7.4
11.2
10.0
6.6
Date
27
18
29
12
1995
8.4
2.0
12.2
25
1996
1997
1998
1999
2000
7.9
7.3
6.0
6.2
4.9
18
21
18
7.0
15
10.4
9.5
6.2
7.3
8.7
27
10
28
31
5
2001
7.0
26
7.9
24
2002
2003
2004
2005
2006
2007
2008
All time
record
5.4
9.4
7.7
8.0
8.3
9.3
6.9
28
1.0
1.0
18
23
15
25
8.3
7.4
10.0
7.4
10.9
10.3
10.5
12
27
19
28
31
30
28
3.3
10 ,1954
3.6
27, 1983
28
26
Temperature (Degree C)
24
Normal
Actual
22
20
18
16
14
12
1s
t
N
8t ove
h
m
15 No be
th v e r
22 No mb
nd ve e r
m
29 No b e
th vem r
N
6t o v b er
h em
D
13 e b e
th c e r
m
20 De be
th cem r
27 De b e
th ce r
De mb
3r cem er
d
b
10 J an er
th ua
17 Jan ry
th ua
24 Jan ry
th ua
31 Jan ry
s t ua
J
7t a n ry
h
u
F
14 e ary
th bru
21 Feb ary
s t ru
28 Feb ary
th ru
Fe ar
br y
ua
ry
10
Date
Fiq.1. Actual (01 Novem ber to 10th Decem ber,2010) and Norm al (Nov to Feb)
Fig.2 Probability (%) of below normal minimum temperature during December 2010
Fig.3 Probability (%) of below normal maximum temperature during December 2010