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IceWeb

User's Guide

Table of Contents

General Information

Chapter 2

Using IceWeb

Observational Data

Viewing Observational Data in a Table
Viewing Observational Data in a graph
Viewing Observational Data on a Map

Forecast Data

Viewing the Regional Forecast Texts
Viewing Forecast Graphs
Viewing Forecast Thermal Maps

Chapter 3

Data Interpretation

Attribute Codes

Observed Road State Bar Colors
Forecast Road State Bar Graph Colors
SSI Road Sensor Surface States
Alarm State
Precipitation State
Cloud State
Freezing Point Temperature
Precipitation and Alarm States
PWD11 States
Forecast Precipitation State
Forecast Cloud Amount
Forecast Cloud Type

General Information

Regulatory Compliances

Vaisala Ltd is accredited to ISO 9001:1994, certificate number FS34153.

Microsoft, Windows, and Windows NT are registered trademarks of Microsoft Corporation in U.S. and/or other countries.

Getting Help

The Vaisala ICE Help Desk is available for any problems or queries you may have with the software. It is operational 24hrs a day, 7 days a week from October to April inclusive and during normal office hours (9.00am-5.00pm Monday to Friday) outside this period.

Telephone (UK) 0121 683 1269

Telephone (International) +44 (121) 683 1269

Toll free (USA) 1 800 408 9457

Email ice.customer.support@vaisala.com

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Using IceWeb

Within IceWeb there are 2 main types of data which can be viewed, observational data from the weather stations and forecast data which includes the forecast graphs and regional texts provided by your forecast provider and also forecast thermal maps.

Within the observational or forecast data options across the top of the screen there are 3 separate options for viewing the data. You can view the observational data in either a table, graph or map and the forecast data in either a text summary, graph or forecast thermal map.

The 2 blue rows with these options on them will remain on the screen at all times to allow easy navigation between the views required.

NOTE

The map options will only be available if you have digital mapping information on your IceWeb server.

Observational Data

The observational data contains the meteoroloical readings from the weather stations. This information can be viewed in either a table, graph or map.

Viewing Observational Data in a Table

Table 3 Viewing Observational Data in a Table

Step	Action
1	To view a table on screen, on the top blue row entitled Observation click on Tables
2	This will bring up a menu entitled Site Table Index down the left hand side of the screen containing various options. There will be two main types of view available, the Status Table view and the individual site table views. To open a Status Table just click on Status Table To open a site table view just click on the name of the site you wish to see the data from.
3	The Status Table option will display the latest meteorological data from all of the weather stations from which you receive data in a tabular format.
4	The site table options (the names of the sites) will bring up the last 24 hours readings from the individual weather stations in a tabular format.

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Viewing Observational Data in a graph

Table 4 Viewing Observational Data in a Graph

Step	Action
1	To view a graph of observational data on screen, on the top blue row entitled Observation click on Graphs
2	This will bring up a menu entitled Site Graph Index down the left hand side of the screen containing the list of the weather stations. To view a site graph for a specific site just click on the the name of the site.
3	The actual readings shown will vary from client to client depending on the initial configuration. On the graph the readings on the right hand side of the graph are the latest readings reported from that site, with the time of that reading displyed on the top right of the graph (in this example the readings are at 14.40) The readings are also color coded to enable you to indentify what readings the various lines represent. On the example here the pink line refers to the surface temperature, the green line to the ground temperature (6cm underground) and the blue line to the depth temperature (30 cm underground).

NOTE

Any non numerical readngs on graphs are displayed on bars across the bottom of the graph. Please see xxxxxx for a full interpretation of the colours.

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Viewing Observational Data on a Map

Table 5 Viewing Observational Data on a Map

Step	Action
1	To view a map showing observational data on screen, on the top blue row entitled Observation click on Maps
2	This will bring up a menu entitled Status Map Index down the left hand side of the screen containing a list of all possible views. Then just click on the name of a view to open it.
3	The map will show the location of your weather stations. The weather stations will change colours depending on tests which will have been set on the IceWeb server. It is advised that you contact your IT department / network administrator for full details of the tests set. In the example here the icons have been configured to turn green if the road surface temperature is above 12 degrees and turn red if the road temperature is below 12 degrees. The current road temperature readings are shown to the top right of the icon. If the weather station has wind instrumentation then the direction from which the prevailing wind is coming from is indicated by the wedges within the circles. In the example here the wind is coming from a south / south westerly direction across the region.
	If an icon is triangular with a red cross through it it means that no data has been received from the weather station within the last 24 hours.
	If an icon is triangular with a yellow cross through it it means that although data has been receibed within the last 24 hours the most recent data has not been received.

NOTE

This view is an optional view. You need a digital map database on the IceWeb server in able to see this view.

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Forecast Data

The forecast data refers to the information sent through from your forecast provider, together with the forecast thermal maps. The information can be viewed as either regional text forecasts, forecast graphs or forecast thermal maps.

Viewing the Regional Forecast Texts

Table 6 Viewing the Regional Forecast Texts

Step	Action
1	To view the regional forecast text, click on the blue row entitled Forecast click on Texts.
2	This will bring up a menu entitled Forecast Text Index down the left hand side of the screen containing a list of all the regional forecast text forecasts. To view a specific forecast click on the forecast required.
3	The forecast will then appear on screen.

NOTE

If the original forecast provided by the forecast provider is in a text format instead of an html format then this will cause some shift in the text layout when the text is converted into an html page by the Iceweb server.

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Viewing Forecast Graphs

Table 7 Viewing Forecast Graphs

Step	Action
1	To view a forecast graph on screen, on the top blue row entitled Forecast click on Graphs
2	This will bring up a menu entitled Forecast Graph Index down the left hand side of the screen containing the list of the forecast weather stations. To view a forecast graph for a specific site just click on the the name of the site
3	The readings shown will vary from client to client, depending on the initial configuration. On the graph the readings on the right hand side of the graph are the latest forecast readings reported from that site. The readings are also color coded to enable you to indentify what readings the various lines represent. Usually the dotted line is the forecast reading and the solid line is the actual reading. On the example here the dotted pink line refers to the forecast surface temperature and the solid pink line the actual surface temperature. Any non-numerical readings are displayed on color coded bars across the bottom of the screen. In this example the bottom bar represents the forecast surface state (FcState)and the top bar represents the actual surface state from the prime sensor (State2, i.e actual surface state from sensor 2 which in this case is the prime sensor).

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Viewing Forecast Thermal Maps

Table 8 Viewing Forecast Thermal Maps

Step	Action
1	To view a forecast graph on screen, on the top blue row entitled Forecast click on Maps
2	This will bring up a menu entitled Thermal Map Index down the left hand side of the screen containing the list of all the thermal map views available. To view a specific thermal map just click on the the name of the map.
3	The forecast thermal map will then appear.
	To access the key to the colors scroll down the screen and the key will be found under the map.

NOTE

This view is an optional view. You need a digital map database on the IceWeb server, thermal mapping data and 24-hour site specific forecasts in able to see this view.

Chapter 3

Data Interpretation

Attribute Codes

To conserve space in tabular views, codes are represented by abbreviations. These are provided here with the bar graph colors.

Observed Road State Bar Colors

Color	Table Code	Condition	Physical Meaning
Green	DRY	Dry	Surface is dry
Light Blue	MOIST	Moist	Surface moist. Typically, asphalt roads will appear darker than normal.
Blue	WET	Wet	Surface wet. Asphalt roads may glisten with reflected light. There may be standing liquid water present on the road.
"Teal" or slate blue	WTRTD	Wet and Treated	Liquid water containing deicing chemical is present on the road surface.
Purple	FROST	Frost	Hoar frost detected. A heavy deposit of frost will leave the road with a coating of white ice crystals, effectively giving an asphalt surface a gray appearance when viewed in daylight.
Light Gray or "Silver"	SNOW	Snow	Snow detected on the road surface.
Red	ICE	Ice	Mono-crystalline ("black") ice detected. Formed by the freezing of water in-situ, this generally comprises a layer of clear ice, so an asphalt road surface will appear black.
Light Green or "Lime"	TRACE	Trace or Moist and Treated	Road surface moist and there is de-icing chemical present. Typically, this is seen when a road is in transition between a "dry" and "moist" or "wet" state, during which there may be thin film of moisture - often generated by residual salt absorbing moisture at high humidities.

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Forecast Road State Bar Graph Colors

Where selected, the colors for the observed data follow those used for the Site Graph view. Colors for the various forecast parameters are shown as a bar.

Color	Condition	Physical Meaning
Green	Dry	Surface dry
Blue	Wet	Surface wet, typically following a period of precipitation
Dark Blue	Wet & Precip	Surface wet and precipitation forecast
Light Blue	Light Dew	Limited deposition of dew expected on the road surface.
"Teal" or slate-blue	Heavy Dew	Significant deposit of dew expected, sufficient the make the surface "Moist" or even "Wet".
Maroon	Light Frost	Limited deposition of hoar frost expected.
Purple	Heavy Frost	Significant deposition of hoar frost expected, sufficient to coat the surface with a continuous layer of ice crystals.
Red	Ice	Ice formation expected on the surface.
Light Gray or "Silver"	Snow	Snow forecast to settle and accumulate on the road surface

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SSI Road Sensor Surface States

Some clients use IceView to inspect data from non-Vaisala sites. The surface states reported from these sites may vary from those reported from Vaisala sites. If these additional SSI (Scan) surface states are reported from a site they will be displayed automatically in tabular views. The user may select to add them to the Forecast Key as well by ticking the ‘Show Supplementary States’ box in the preferences window. The following table indicates the surface states reported from Scan SSI sites.

Table code	SSI status title	SSI Definition
DRY	Dry	No moisture on the road / runway surface.
WET	Wet	Wet road / runway surface above 0° C/32° F.
DEW	Dew	Moisture present on road/runway surface; surface temperature equal to or less than dew point and above 0° C / 32° F.
FROST	Frost	Moisture present on road/runway surface; surface temperature equal to or less than dew point and at or below 0° C/32° F.
FADWP	Frost above dew point	Previously frost, but the surface temperature has now moved above dew point.
ABSOR	Absorption	Absorption of moisture into chemicals on the road / runway surface – appears dry or slightly damp. Surface temperature is above dew point.
ABDWP	Absorption at dew point	Absorption of moisture into chemicals on the road / runway surface – appears dry or slightly damp. Surface temperature is at dew point.
ALERT	Surface alert	Precipitation/moisture present in liquid form on road / runway surface. Surface temperature at or below 0° C / 32° F.
CRIT	Surface critical	Surface temperature at or below 0° C / 32° F either: Precipitation / moisture in liquid form on road / runway surface starting to freeze Or Precipitation / moisture on road / runway surface which has frozen
PRDRY	Probable drying	No precipitation detected in the last 4 hours. No chemical present and the surface temperature is rising.

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Alarm State

The alarm states are generated by the weather station, on the basis of the data from each road sensor combined with reports of precipitation, dew point temperature etc. The alarm and warning levels therefore apply to individual road sensors, not the station as a whole. The worst case state is always reported. Hence Frost and Rain Warnings may be overridden by the Ice Warning, which may in turn be overridden by an Ice Alarm.

Color	Table code	Condition	Physical Meaning
Green		None	No Warnings or Alarms
Blue	PRECIP	Precip Warning	Precipitation (rain, snow etc.) detected recently and there may be subsequent freezing, as the surface temperature is close to or below freezing.
Purple	FRSTW	Frost Warning	Surface temperature is below freezing and below the dew point temperature. Hence hoar frost is either present or can be expected to form shortly.
Magenta	WARN	Ice Warning	Surface is close to freezing or ice and or frost formation will occur within a given period if the current trend continues.
Red	ALARM	Ice Alarm	Surface at or below freezing point; either there is ice / frost already or there will be very soon.

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Precipitation State

Not all reports may be present on any single system, depending on the type of precipitation detectors fitted to the outstations. Older types of equipment were limited to "Recent Precip" and "Current Precip". Only those systems equipped with a PWD11 or FD12P present weather sensor will report the snow states. The precipitation intensity is measured over the ten-minute period prior to the observation and that precipitation has to persistent for the intensity to be shown. If the station is not able to estimate the intensity, as may happen in the event of intermittent, light precipitation, "Recent Precip" may be reported.

Color	Table code	Condition	Physical Meaning
Green		None	No Precipitation
Blue	RECNT	Recent Precip	Precipitation occurred between the previous observation and this latest report.
Dark Blue	NOW	Current Precip	Precipitation reported at the time of observation.
Light Blue	LIGHT	Light Precip	Intensity less than 2mm per hour
Blue	MED	Medium Precip	Intensity in the range 2-4mm per hour
Dark Blue	HEAVY	Heavy	Intensity greater than 4mm per hour
Yellow	LSNOW	Light Snow	Intensity as above but for frozen precipitation and for water equivalent.
"Silver" or Light Gray		Medium Snow	Moderate intensity, frozen precipitation.
Gray	HSNOW	Heavy Snow	Heavy snowfall, rapid accumulation.

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Cloud State

This data is only available from the later generation station types and is an approximate indicator of the cloud state at the sensor location. Badly shaded sensors may lead to incorrect estimates.

Color	Table code	Condition	Physical Meaning
Blue	PRECIP	Precip	Sky cloudy (>5-8ths) and precipitation reported
Gray	CLOUD	Cloudy, no precip	Sky cloudy but no precipitation.
Light Blue	CLEAR	Clear	No cloud or well-broken cloud cover (4/8ths or less).
Green	NO RN	No Rain	Indeterminate cloud state but no precipitation.

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Freezing Point Temperature

The estimated freezing point temperature is used to indicate the amount of de-icing chemical present on the surface. However, the measurement is only practical under moist or wet conditions; in dry conditions the freezing point temperature will always return to 0ºC (32°F).

Where salt-based de-icing agents are used, the position is complicated by the hygroscopic nature of salt: at humidities greater than about 80%, the salt on the road will tend to absorb moisture, leading to perhaps reports of "Trace", "Moist" or "Wet" surface but with small freezing point depressions.

Due to the difficulty of measuring the amount of de-icing chemical accurately, and the small sample volume represented by the sensor head, this data should always be interpreted with care.

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Precipitation and Alarm States

The data shown under the "RainSt" and "Alarm" columns in tabular displays may often appear to be absent. The usual condition in either case is "None" i.e. no precipitation and no alarms. When this applies, the field in the table will be blank. A positive state will fill that field with the appropriate text e.g. "RECNT" (Recent Precipitation) or "FROST" (Frost Warning).

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PWD11 States

The data shown under the 'PWthr' column in tabular displays may appear to be absent. If there is no precipitation the column will be blank. Otherwise, the PWD11 will report the precipitation type as best it can, using one of the codes given below. Occasionally, the type of precipitation cannot be resolved in which case the sensor will report one of the "precipitation" states. This may be the case for example where the precipitation started shortly before the time the data was collected.

PWthr Condition	Physical Meaning
L Ppt	Light Precipitation
M Ppt	Medium Precipitation
H Ppt	Heavy Precipitation
Rain	Rain
Lrain	Light Rain
Mrain	Moderate Rain
Hrain	Heavy Rain
Ice P	Ice Pellets
L Slt	Light Sleet
Sleet	Moderate Sleet
Snow	Snow
Lsnow	Light Snow
Msnow	Moderate Snow
Hsnow	Heavy Snow

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Forecast Precipitation State

Color	Condition	Physical Meaning
Green	No Precip
Aqua	Light	Light rain or drizzle expected during the period shown.
"Teal" or slate-blue	Medium	Moderate rain or showers forecast.
Blue	Heavy	Continuous moderate to heavy rain or heavy showers.
Yellow	Light Snow	Light sleet or snowfall.
Silver	Medium Snow	Moderate snowfall.
Gray	Heavy Snow	Heavy sleet or snow forecast, typically resulting in accumulation on the road surface.

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Forecast Cloud Amount

Color	Condition	Physical Meaning
Light Blue	No Cloud
Yellow	1 Octa	Very patchy, isolated clouds.
Magenta	2 Octas	Patchy cloud.
Light Green	3 Octas	Patchy cloud but clouds starting to cluster or group together
Silver	4 Octas	Half the sky occupied by cloud
Teal	5 Octas	Majority of the sky occupied by cloud
Maroon	6 Octas	Sky generally cloudy
Gray	7 Octas	Essentially continuous cloud with occasional breaks
Purple	8 Octas	Continuous cloud cover.
Red	9 Octas	Sky obscured i.e. continuous and / or thick fog.

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Forecast Cloud Type

Color	Condition	Physical Meaning
Blue	No Cloud
Purple	Low Cloud	Cloud base less than approx. 1500m above ground level.
Gray	Medium Cloud	Cloud base in the general range 1500-3000m above ground level.
Yellow	High Cloud	Cloud base greater than approximately 3000m above ground level.

November 2001

© Vaisala 2002

No part of this manual may be reproduced in any form or by any means, electronic or mechanical (including photocopying), nor may its contents be communicated to a third party without prior written permission of the copyright holder.

The contents are subject to change without prior notice.