Temperature
56 F at 1 AM; 79 F at its warmest, 3 PM Thursday, and 56 F at its coolest, 1 AM.
- Now
- 56F
- 1 AM
- Highest
- 79F
- 3 PM Thursday
- Lowest
- 56F
- 1 AM
How it is measured: Stevenson screen and siting, Field Book FB-INS-009
St Louis Regional Airport, Illinois
Medium airport in Madison County, Illinois50°
58°/45°
Overcast·
Feels like 44°·Moderate breeze 15 mph NW
Now. St Louis Regional Airport is 50° and overcast at 2 AM. With the wind it feels like 44°. The dew point is 51°, so the air feels dry and comfortable. Moderate breeze from the northwest at 15 mph.
Today and tonight. It warms to about 58° by 3 PM. Tonight falls to about 37° by 7 AM, under a mostly clear sky.
The week. The warmest day ahead is Thursday, near 80°, and the coolest tomorrow, near 60°. The days ahead look dry. Frost is possible Sunday morning, a low of 34°.
The sky tonight. The sun sets at 6:20 PM. The Moon is a waxing crescent, 33% lit, and sets at 10:20 PM. The next full Moon is Sunday, Oct 25. After dark, look for Saturn, bright in the east-southeast. A planet shines with a steady light where the stars around it twinkle. The Orionids meteor shower is active, peaking around Oct 21: at its peak, up to about 20 meteors an hour can be seen from a dark site. The sky is forecast to stay clear: a good night to look up. The day is 11 hours 11 minutes long, 3 minutes shorter than yesterday.
0UV Low
17Air quality
85%Humidity
100%Cloud
Now
2:00 AM
50feels44
23%
15mph
Today
Oct 16
5845
23%
20mph
Sat
Oct 17
6037
12mph
UV 6
Sun
Oct 18
6634
UV 6
Mon
Oct 19
7238
overcast
Tue
Oct 20
7541
overcast
Wed
Oct 21
7845
overcast
Thu
Oct 22
8048
overcast
50°
58°45°
60°37°
66°34°
72°38°
75°41°
78°45°
80°48°
As of 2:00 AM in St Louis Regional Airport, Illinois.
Air quality
The air at St Louis Regional Airport
Index 17, good, led by ozone. Read at 1 AM from its reporting area, St. Louis (Metro-east) (IL), 22 miles off.
17Good
- Fine particles (PM2.5)10Good-
- Ozone17Good-
- Coarse particles (PM10)4Good-
The days ahead
Good each day through Mon Oct 19, led by fine particles. Yesterday measured 39, good.
GoodModerate
- 39YesterdayOct 15
- GoodTodayOct 16
- GoodSatOct 17
- GoodSunOct 18
- GoodMonOct 19
Smoke, the next 42 hours
No smoke near the ground through Sat 7 PM.
Precipitation
What has fallen at St Louis Regional Airport
0.30 in in the last 24 hours, 1.35 in over the last 3 days, to Fri 1 AM. Measured by radar and rain gauges, as water.
- Last 24 hours
- 0.30in
- Last 3 days
- 1.35in
3 days agoLast 24 hours 22%
Visibility
How far you can see at St Louis Regional Airport, the next 42 hours
Visibility stays 9 miles or more through Sat 7 PM, lowest 9 miles Fri 4 PM.
F
Now, today, and the week
Weather instrument stations by state
Airfield
- Code
- ALN
- ICAO
- KALN
- IATA
- ALN
- Field elevation
- 544 ft
- Serves
- Alton/St Louis
- Kind
- Medium airport
- Scheduled service
- No
- Its own instrument
- ALN
- Wind now
- From 300° at 17 mph, read 16 Oct, 01:55
Runways
| Runway | Length | Width | Surface | Heading, true | Wind along it now | Crosswind now |
|---|---|---|---|---|---|---|
| 11 / 29 | 8,099 ft | 150 ft | Asphalt | 113° / 293° | 17 mph head, on 29 | 2 mph from the right |
| 17 / 35 | 6,500 ft | 100 ft | Asphalt | 174° / 354° | 10 mph head, on 35 | 14 mph from the left |
Measured here
What the airfield's own instrument measured, the last 24 hours
Every hour from Alton/St Louis R (ALN), St Louis Regional Airport's own instrument, measure by measure, on the field's own clock.
Humidity and dew point
A dew point of 52 F, the air 86% saturated; the humidity ran from 70% at 5 PM Thursday to 95% at 6 AM Thursday.
- Dew point now
- 52F
- 1 AM
- Humidity now
- 86%
- Humidity, range
- 70 to 95%
How it is measured: Humidity variables, Field Book FB-WAT-002
Wind
15 mph from the west northwest at 1 AM; at its strongest 23 mph, 10 PM Thursday, with a gust of 36 mph at 10 PM Thursday.
- Now
- 15mph
- from the west northwest
- Strongest
- 23mph
- 10 PM Thursday
- Highest gust
- 36mph
- 10 PM Thursday
How it is measured: Coriolis as geometry, Field Book FB-ENG-008
Pressure
30.10 inHg at 1 AM, rising 0.11 inHg over 3 hours; 0.05 inHg higher than a day before.
- Now
- 30.10inHg
- 1 AM
- 3 hours
- +0.11inHg
- rising
- 24 hours
- +0.05inHg
How it is measured: Hydrostatic balance, Field Book FB-ENG-003
Visibility
Down to 2 miles at 9 AM Thursday; 10 miles or more now.
- Now
- 10+mi
- Lowest
- 2mi
- 9 AM Thursday
- Hours under a mile
- 0
How it is measured: Fog types, Field Book FB-WAT-020
Cloud base
The lowest cloud base came down to 300 ft at 6 AM Thursday; a base was reported in 21 of the hours.
- Lowest base now
- -
- Lowest in 24 hours
- 300ft
- 6 AM Thursday
- Hours with a base reported
- 21
How it is measured: Cloud classification, Field Book FB-SKY-001
Precipitation
None measured in the gauge in the last 24 hours.
- Last 24 hours
- 0.00in
- Wettest hour
- -
- Hours with some
- 0
How it is measured: ASOS, Field Book FB-INS-002
Alton/St Louis R: every reading, the last 7 days, 30 days and the year, and how well it reports
What is measuring near here
The 5 instruments nearest St Louis Regional Airport, how far away each one is, how high it stands, and what kind of measurement it makes. The nearest is 0.0 miles away.
measured now3 instruments
At an airfield/0.0 mi away/545 ft/1 ft above here
temp, wind, gust, visibility, precip, pressure
US-67 @ Clark BridgeSS0110
Beside a road/6.8 mi away/-/- ft from here
temp, pavement temp, wind, visibility, precip
Mississippi River AT Mel Price LDALNI2
At a river or reservoir gauge/7.4 mi away/394 ft/150 ft below here
temp, wind, gust, humidity, pressure
measured daily2 instruments
Bethalto 0.9 NWIL-MD-54
In a volunteer observer's own ground/1.6 mi away/530 ft/14 ft below here
precip, snowfall, snow depth
AltonALNI2
At a cooperative observer's station/7.4 mi away/394 ft/150 ft below here
snowfall, snow depth, precip, high, low
What the snow tracker reads here
Every instrument in this state
0in
Snow on the ground
Measured at Mississippi River AT Mel Price LD (ALNI2), 7.4 miles from here, read 15 Oct, 05:00. measured daily
Elsewhere in Illinois
23 places, each with its own forecast and its own instruments.
AuroracityBloomingtoncityCarbondalecityChampaigncityChicagocityDanvillecityDecaturcityElgincityGalenatownIllinois RiverfeatureJolietcityLake ShelbyvillefeatureMolinecityMount VernoncityNapervillecityPeoriacityQuincycityRockfordcityShawnee National ForestfeatureSpringfieldcityStarved RockfeatureVilla Oliviaski areaWaukegancity
Near St Louis Regional Airport
The nearest places, each with its own forecast and the instruments nearest it.
- Bethaltovillage, 1 mi
- Rosewood Heightscommunity, 1 mi
- Morocommunity, 3 mi
- Wood Rivercity, 3 mi
- East Altonvillage, 3 mi
- Roxanavillage, 3 mi
- South Roxanavillage, 4 mi
- Hartfordvillage, 5 mi
- Altoncity, 6 mi
- Holiday Shorescommunity, 6 mi
- Edwardsvillecity, 8 mi
- Prairietowncommunity, 9 mi
Airports near St Louis Regional Airport
- St Louis Downtown AirportCPS, 23 mi
- Scott AFB/Midamerica AirportBLV, 26 mi
- Litchfield Municipal Airport3LF, 27 mi
- Sparta Community Airport - Hunter FieldSAR, 55 mi
- Centralia Municipal AirportENL, 58 mi
- Taylorville Municipal AirportTAZ, 59 mi
- Salem-Leckrone AirportSLO, 61 mi
- Jacksonville Municipal AirportIJX, 62 mi